Dissertations / Theses: 'Three dimensional space'

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Tucker, Andrew James, and n/a. "Visual space attention in three-dimensional space." Swinburne University of Technology, 2006. http://adt.lib.swin.edu.au./public/adt-VSWT20070301.085637.

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Current models of visual spatial attention are based on the extent to which attention can be allocated in 2-dimensional displays. The distribution of attention in 3-dimensional space has received little consideration. A series of experiments were devised to explore the apparent inconsistencies in the literature pertaining to the allocation of spatial attention in the third dimension. A review of the literature attributed these inconsistencies to differences and limitations in the various methodologies employed, in addition to the use of differing attentional paradigms. An initial aim of this thesis was to develop a highly controlled novel adaptation of the conventional robust covert orienting of visual attention task (COVAT) in depth defined by either binocular (stereoscopic) or monocular cues. The results indicated that attentional selection in the COVAT is not allocated within a 3-dimensional representation of space. Consequently, an alternative measure of spatial attention in depth, the overlay interference task, was successfully validated in a different stereoscopic depth environment and then manipulated to further examine the allocation of attention in depth. Findings from the overlay interference experiments indicated that attentional selection is based on a representation that includes depth information, but only when an additional feature can aid 3D selection. Collectively, the results suggest a dissociation between two paradigms that are both purported to be measures of spatial attention. There appears to be a further dissociation between 2-dimensional and 3-dimensional attentional selection in both paradigms for different reasons. These behavioural results, combined with recent electrophysiological evidence suggest that the temporal constraints of the 3D COVAT paradigm result in early selection based predominantly on retinotopic spatial coordinates prior to the complete construction of a 3-dimensional representation. Task requirements of the 3D overlay interference paradigm, on the other hand, while not being restricted by temporal constraints, demand that attentional selection occurs later, after the construction of a 3-dimensional representation, but only with the guidance of a secondary feature. Regardless of whether attentional selection occurs early or late, however, some component of selection appears to be based on viewer-centred spatial coordinates.

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Tucker, Andrew James. "Visual space attention in three-dimensional space." Australasian Digital Thesis Program, 2006. http://adt.lib.swin.edu.au/public/adt-VSWT20070301.085637/index.html.

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Thesis (PhD) - Faculty of Life and Social Sciences, Swinburne University of Technology, 2006.
Submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy, Faculty of Life and Social Sciences, Swinburne University of Technology - 2006. Typescript. "March 2006". Includes bibliographical references (p. 153-173).

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Minor, Sue Blose. "Children's understanding of projective space in two-dimensional representations of three-dimensional space /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487688973683519.

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Fazai, Sallouha. "Three-Dimensional Space to Assess Cloud Interoperability." Monterey, California. Naval Postgraduate School, 2013. http://hdl.handle.net/10945/32818.

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Cloud computing is an emerging technology that promises the reduction of IT costs (personnel, software, and hardware) for enterprises, as well as individual users. Despite this appealing offer, this technology has still not been widely adopted in the enterprise IT. Users are still worried about vendor lock-in; they will not be able to move their data and applications from one cloud provider to another easily or return to in-house IT. Currently, users do not have the means to specify and assess the interoperability level of the cloud provider that they desire to entrust their IT operations. In this thesis work, we provide a three-dimensional space to assess and visualize the interoperability level of any cloud provider so that cloud users can select the providers services that better fit their interoperability needs.

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Shonoda, Emad N. Naseem. "On Ruled Surfaces in three-dimensional Minkowski Space." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2010. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-63555.

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In a Minkowski three dimensional space, whose metric is based on a strictly convex and centrally symmetric unit ball , we deal with ruled surfaces Φ in the sense of E. Kruppa. This means that we have to look for Minkowski analogues of the classical differential invariants of ruled surfaces in a Euclidean space. Here, at first – after an introduction to concepts of a Minkowski space, like semi-orthogonalities and a semi-inner-product based on the so-called cosine-Minkowski function - we construct an orthogonal 3D moving frame using Birkhoff’s left-orthogonality. This moving frame is canonically connected to ruled surfaces: beginning with the generator direction and the asymptotic plane of this generator g we complete this flag to a frame using the left-orthogonality defined by ; ( is described either by its supporting function or a parameter representation). The plane left-orthogonal to the asymptotic plane through generator g(t) is called Minkowski central plane and touches Φ in the striction point s(t) of g(t). Thus the moving frame defines the Minkowski striction curve S of the considered ruled surface Φ similar to the Euclidean case. The coefficients occurring in the Minkowski analogues to Frenet-Serret formulae of the moving frame of Φ in a Minkowski space are called “M-curvatures” and “M-torsions”. Here we essentially make use of the semi-inner product and the sine-Minkowski and cosine-Minkowski functions. Furthermore we define a covariant differentiation in a Minkowski 3-space using a new vector called “deformation vector” and locally measuring the deviation of the Minkowski space from a Euclidean space. With this covariant differentiation it is possible to declare an “M-geodesicc parallelity” and to show that the vector field of the generators of a skew ruled surface Φ is an M-geodesic parallel field along its Minkowski striction curve s. Finally we also define the Pirondini set of ruled surfaces to a given surface Φ. The surfaces of such a set have the M-striction curve and the strip of M-central planes in common

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Kim, Misun. "Three-dimensional space representation in the human brain." Thesis, University College London (University of London), 2018. http://discovery.ucl.ac.uk/10053145/.

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Brain structures that support spatial cognition by encoding one’s position and direction have been extensively studied for decades. In the majority of studies, neural substrates have been investigated on a horizontal two-dimensional plane, whereas humans and other animals also move vertically in a three-dimensional (3D) world. In this thesis, I investigated how 3D spatial information is represented in the human brain using functional MRI experiments and custom-built 3D virtual environments. In the first experiment, participants moved on flat, tilted-up or tilted-down pathways in a 3D lattice structure. Multivoxel pattern analysis revealed that the anterior hippocampus expressed 3D location information that was similarly sensitive to the vertical and horizontal axes. The retrosplenial cortex and posterior hippocampus represented direction information that was only sensitive to the vertical axis. In the second experiment, participants moved in a virtual building with multiple levels and rooms. Using an fMRI repetition suppression analysis, I observed a hierarchical representation of this 3D space, with anterior hippocampus representing local information within a room, while retrosplenial cortex, parahippocampal cortex and posterior hippocampus represented room information within the wider building. As in the first experiment, vertical and horizontal location information was similarly encoded. In the last experiments, participants were placed into a virtual zero-gravity environment where they could move freely along all 3 axes. The thalamus and subiculum expressed horizontal heading information, whereas retrosplenial cortex showed dominant encoding of vertical heading. Using novel fMRI analyses, I also found preliminary evidence of a 3D grid code in the entorhinal cortex. Overall, these experiments demonstrate the capacity of the human brain to implement a flexible and efficient representation of 3D space. The work in this thesis will, I hope, serve as a stepping-stone in our understanding of how we navigate in the real – 3D – world.

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Jovalekic, A. T. "Anisotropic usage and encoding of three-dimensional space." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1348573/.

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Decades of work in the field of spatial cognition have revealed fundamental aspects of how navigation is structured in two-dimensional, horizontal spaces and have exposed remarkable insights into how the brain processes spatial information. However, animals and humans daily encounter navigation tasks in complex environments that include many vertical features. Until now, it has been only poorly understood how navigation behaviours are organised in three-dimensional spaces and how the additional vertical dimension is encoded. The aim of the present thesis was threefold: first, to review behavioural and neurophysiological literature involving three-dimensional navigation; second, to characterise spatial behaviours in environments with a vertical dimension; and third, to study neural substrates of three-dimensional navigation. Rats’ navigation abilities were tested in two types of environments: the pegboard, which is a vertical climbing wall, and the lattice maze, which is a three-dimensional climbing cube. Foraging and detour experiments were conducted in both environments and revealed that the use of three-dimensional space is horizontally biased. Such biases were manifested in three ways. Rats exhibited more horizontal than vertical movements, structured their foraging behaviours in a horizontal fashion and showed preference for initially-horizontal paths when offered two routes requiring equivalent effort to reach a goal. In order to understand how the vertical dimension is represented at a neural level, hippocampal place cells and entorhinal grid cells were recorded on the pegboard during foraging. In horizontal environments, place cells exhibit location-specific firing, whereas grid cells map space with multiple hexagonally arranged firing fields. The experiments with the pegboard revealed that both cell types represented the horizontal dimension better than the vertical dimension. Furthermore, grid cells formed vertically aligned stripes on the pegboard, suggesting that encoding of the vertical dimension was more strongly impaired in grid cells than by place cells. It is suggested that in rats, three-dimensional spaces are – both at a neural and a behavioural level – anisotropically represented.

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Verriotis, M. A. "Exploring the brain's representation of three-dimensional space." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1339146/.

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Previous research has shown that in two‐dimensional environments, ‘place cells’ and ‘grid cells’ in the hippocampal formation comprise two units of O’Keefe and Nadel’s (1978) ‘cognitive map’, coding for the rat’s present location and for metric distance information, respectively. Since the world is three‐dimensional, an important question is whether the cognitive map is also volumetric. To explore this issue, place and grid cells were recorded from rats as they shuttled up and down between two ends of a spiral staircase (the ‘helical track’), allowing the same horizontal locations to be sampled at different vertical levels. Using this novel paradigm, it was possible to investigate whether place and grid cell receptive fields are globular or planar. The first experiment demonstrated that place fields extended in the vertical, as well as horizontal, dimension, suggesting that they were globular. However, the vertical extent was larger than the horizontal extent, suggesting either a coarser representation of height, or contextual modulation of fields in the vertical dimension, in the absence of metric vertical distance. Both possibilities imply that the cognitive map is anisotropic (not uniform in all dimensions). The second set of experiments involved probe trials that showed that both distal and local cues influence place fields in the vertical dimension. The third experiment demonstrated that grid cells produced several subfields on the helical track that, similar to the place fields, were vertically elongated. However, they were more elongated than place fields, and showed no vertical periodicity, suggesting the lack of metric vertical information. Overall, these observations suggest that three‐dimensional space is anisotropically represented in the rat brain as a contextually modulated flat map, in which only the current navigation plane is metrically represented. Due to the complexity of a truly three‐dimensional representation, an anisotropic representation is likely in all surface‐navigating animals including humans.

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Nussbaum, Doron Carleton University Dissertation Computer Science. "Directional separability in two and three dimensional space." Ottawa, 1988.

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Sitter, David Norbert. "Space invariant modeling in three-dimensional optical image formation." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/13450.

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Shepard, William Steve Jr. "Active noise control in a three dimensional half space." Thesis, Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/17547.

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Marshall, Jeffrey Barrett. "A World Wide Web browser utilizing three-dimensional space." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/41384.

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Benveniste, David 1977. "Cognitive conflict in learning three-dimensional space station structures." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/26750.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2004.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
"September 2004."
Includes bibliographical references (p. 87-88).
(cont.) reached very high values early in the experiment and was significantly but slightly lower in FC than in GC. The target position relative to the subject's body did not affect performance, but subjects responded significantly faster when they were visually upright than when they were upside-down. Although alternative explanations cannot be ruled out, data collected and subjects' comments suggest that unlearning the GC cognitive map posed a significant challenge, and that subjects' knowledge of modules in GC, acquired earlier in the experiment, impeded their learning in FC, at least for the complex FC we used. Results of a Perspective Taking Ability test correlated weakly but significantly with TTR performance in GC, but not in FC. Other tests of spatial skills showed no significant correlation with performance. The effects of motion sickness susceptibility and of gender are also discussed. Supported by NASA Cooperative Agreement NCC 9-58 with the National Space Biomedical Research Institute.
Astronauts train on the ground in normal gravity, in replicas of the space station. Physical constraints force the configuration of these modules on the ground to be different from the configuration of the space station in flight. Based on descriptions of mishaps in human wayfinding (Jonsson 2002), it was hypothesized that the cognitive map of the space station formed from the replicas on the ground could be hard to unlearn. Could the resulting conflict with the actual configuration in flight explain why astronauts lack survey knowledge and often lose track of their orientation? Can they be trained using virtual reality to learn the correct configuration? What makes a configuration hard to learn or unlearn? We studied the ability to learn two realistic and polarized cubic modules in immersive virtual reality. Subjects (n=19) learned these modules first separately, then attached in two different configurations: first a "ground configuration" (GC), then a "flight configuration" (FC). The intrinsic visual verticals of both modules matched in GC, but not in FC, and walls at the interface between the modules were different in the two configurations. Subjects received guided tours of the modules and, through repeated trials, had to predict the location and orientation of one wall (the target), using the wall they were facing. The environment was pseudo-randomly rotated between trials. In the two module environments, subjects were set in the first module and had to place and orient the target wall in the second. The total time to respond to each trial (TTR) and the percent of correct responses (%-correct) were measured. The TTR decreased continuously with time within each virtual environment, but was significantly larger in FC than in GC. %-Correct
by David Benveniste.
S.M.

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Hall, Jennifer A. "The human interface in three dimensional computer art space." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/74325.

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Thesis (M.S.V.S.)--Massachusetts Institute of Technology, Dept. of Architecture, 1986.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND ROTCH
Bibliography: leaves 61-68.
by Jennifer A. Hall.
M.S.V.S.

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Stenglin, Maree K. "Packaging curiosities towards a grammar of three-dimensional space /." Connect to full text, 2004. http://hdl.handle.net/2123/635.

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Thesis (Ph. D.)--University of Sydney, 2004.
Title from title screen (viewed 14 May 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Dept. of Linguistics, Faculty of Arts. Includes bibliographical references. Also available in print form.

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Stenglin, Maree Kristen. "Packaging curiosities : towards a grammar of three-dimensional space." Thesis, The University of Sydney, 2004. http://hdl.handle.net/2123/635.

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Western museums are public institutions, open and accessible to all sectors of the population they serve. Increasingly, they are becoming more accountable to the governments that fund them, and criteria such as visitation figures are being used to assess their viability. In order to ensure their survival in the current climate of economic rationalism, museums need to maintain their audiences and attract an even broader demographic. To do this, they need to ensure that visitors feel comfortable, welcome and secure inside their spaces. They also need to give visitors clear entry points for engaging with and valuing the objects and knowledge on display in exhibitions. This thesis maps a grammar of three-dimensional space with a strong focus on the interpersonal metafunction. Building on the social semiotic tools developed by Halliday (1978, 1985a), Halliday and Hasan (1976), Martin (1992) and Matthiessen (1995), it identifies two interpersonal resources for organising space: Binding and Bonding. Binding is the main focus of the thesis. It theorises the way people's emotions can be affected by the organisation of three-dimensional space. Essentially, it explores the affectual disposition that exists between a person and the space that person occupies by focussing on how a space can be organised to make an occupant feel secure or insecure. Binding is complemented by Bonding. Bonding is concerned with the way the occupants of a space are positioned interpersonally to create solidarity. In cultural institutions like museums and galleries, Bonding is concerned with making visitors feel welcome and as though they belong, not just to the building and the physical environment, but to a community of like-minded people. Such feelings of belonging are also crucial to the long-term survival of the museum. Finally, in order to present a metafunctionally diversified grammar of space, the thesis moves beyond interpersonal meanings. It concludes by exploring the ways textual and ideational meanings can be organised in three-dimensional space.

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Stenglin, Maree Kristen. "Packaging curiosities : towards a grammar of three-dimensional space." University of Sydney. Linguistics, 2004. http://hdl.handle.net/2123/635.

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Western museums are public institutions, open and accessible to all sectors of the population they serve. Increasingly, they are becoming more accountable to the governments that fund them, and criteria such as visitation figures are being used to assess their viability. In order to ensure their survival in the current climate of economic rationalism, museums need to maintain their audiences and attract an even broader demographic. To do this, they need to ensure that visitors feel comfortable, welcome and secure inside their spaces. They also need to give visitors clear entry points for engaging with and valuing the objects and knowledge on display in exhibitions. This thesis maps a grammar of three-dimensional space with a strong focus on the interpersonal metafunction. Building on the social semiotic tools developed by Halliday (1978, 1985a), Halliday and Hasan (1976), Martin (1992) and Matthiessen (1995), it identifies two interpersonal resources for organising space: Binding and Bonding. Binding is the main focus of the thesis. It theorises the way people�s emotions can be affected by the organisation of three-dimensional space. Essentially, it explores the affectual disposition that exists between a person and the space that person occupies by focussing on how a space can be organised to make an occupant feel secure or insecure. Binding is complemented by Bonding. Bonding is concerned with the way the occupants of a space are positioned interpersonally to create solidarity. In cultural institutions like museums and galleries, Bonding is concerned with making visitors feel welcome and as though they belong, not just to the building and the physical environment, but to a community of like-minded people. Such feelings of belonging are also crucial to the long-term survival of the museum. Finally, in order to present a metafunctionally diversified grammar of space, the thesis moves beyond interpersonal meanings. It concludes by exploring the ways textual and ideational meanings can be organised in three-dimensional space.

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Slingsby, Aiden David. "Digital mapping in three dimensional space : geometry, features and access." Thesis, University College London (University of London), 2006. http://discovery.ucl.ac.uk/1445099/.

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Demand for large-scale digital vector base mapping is high, fuelled by developments in geographical information systems (GIS), spatial databases, and location-aware devices. The representation of real-world features (e.g. buildings, gardens, sheds), their properties and the spatial relationships between them are essential for supporting these types of applications and they provide an enduring focus for GIS research. There is an increasing and inevitable demand for three-dimensional (3D) however, many currently-available 3D data tend to focus on visualisation aspects, making them unsuitable for populating 3D feature-based databases for spatial analysis. The thesis considers how 3D data can be structured in order that it may be used to support applications in a GIS context. The guiding design principles used to develop the conceptual model are: establishment of a data repository to which information can be added in an in cremental fashion (in order that progress can be made without the requirement of exhaustive 3D surveys) storage of 3D geometry (facilitating the representation of complex multistorey and juxtaposed building parts) ability to describe different conceptualisations of features (e.g. 'rooms' and 'flats') and the relationships between them seamless treatment of space exterior and interior to buildings (in order to treat all space with equivalence) incorporate pedestrian accessibility (spaces are topologically connected and pedestrian access constraints are embedded) representation of a temporal dimension. The key concept is that of 'urban spaces' (discrete units of space in which human activity can occur) inside and outside buildings within the 3D environment. These are organised into layers whose surface geometries are interpolated, even where height data are poorly resolved. The thesis develops a conceptual model, implements a prototype and then illustrates its use for various applications. Particular emphasis is placed upon applications which require pedestrian access information and the definition and identification of 'spaces' and 'real-world features' in 3D built environments.

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Richards, Jason T. (Jason Todd) 1975. "Three-dimensional spatial learning in a virtual space station node." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/69233.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2000.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 77-78).
Astronauts find it difficult to recognize their orientation while facing any of the viewing directions in 6-ported space station node modules. Our previous experiments tested the spatial memory of human subjects in 1-G in an analogous cubic virtual environment and showed that humans are able to learn to orient when instructed to imagine different body orientations while facing in two different directions. Can subjects do the task when facing in all 6 directions? Does training help? Does spatial memory depend on the direction of remembered targets relative to the body? Does performance depend on the subject's ability to rotate himself mentally and use imagery? How long is ability retained after training? 3D spatial learning was studied in two virtual cubic chambers, in which a picture of an animal was drawn on each wall. Through trial-by-trial exposures to a virtual chamber, subjects (n=24) had to memorize the spatial relationships among the 6 pictures around them and learn to predict the direction to a specific picture if they were facing any wall in any roll orientation. After learning in one chamber, the procedure was repeated in a second. Before being tested, subjects received computer-based instructions and practice. Half of subjects were taught to remember logical picture groupings (strategy), while the remaining (control) subjects were free to do the task as they saw fit. Subjects' retention of configurational knowledge (both chambers) and spatial ability (second chamber only, without feedback) were re-tested 1, 7, and 30 days after initial training. Response time (RT) and percent correct (% correct) learning curves were measured on all four days, while configurational knowledge was tested on the last three. All subjects ultimately learned to do the task within 36 trials in either test environment, but performed faster in the second environment than in the first (especially the strategy-trained group). The strategy group showed superior % correct and RT for above/behind targets and generally better configurational knowledge. Retention of configurational knowledge and spatial ability for both groups was good over 30 days. The subjects who reported using mental imagery (n=8) had higher scores on figure rotation tests and % correct for left/right targets. Performances by the control group on the experimental tasks were significantly correlated with those on conventional tests of field independence and 2/3D figure rotation ability. Strategy training helped those who had poorer mental rotation skills, and those who could not use mental imagery. Supported by NASA Cooperative Agreement NCC9-58 with the National Space Biomedical Research Institute, USA.
by Jason T. Richards.
S.M.

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Jackway, Paul Thomas. "Morphological scale-space with application to three-dimensional object recognition." Thesis, Queensland University of Technology, 1994.

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Vohra, Neeru Rani. "Three dimensional statistical graphs, visual cues and clustering." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ56213.pdf.

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Huish, Gary John. "Renormalization of interacting quantum field theory in three dimensional curved space." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240852.

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Walker, Scott J. I. "A study of three dimensional tape spring folds for space applications." Thesis, University of Southampton, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416051.

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VATH, BETINA. "UNION OF BALLS, MEDIAL AXIS AND DEFORMATIONS IN THREE-DIMENSIONAL SPACE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2007. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=10670@1.

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CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
O eixo medial é uma descrição compacta de um objeto que preserva sua topologia e induz naturalmente uma discretização da sua forma como união de bolas. O estudo de união de bolas possui aplicações em diversas áreas da Matemática, em particular na Geometria Computacional onde se usa, por exemplo, para reconstrução de curvas e superfícies. Este trabalho pretende utilizar união de bolas para simular deformações a partir do eixo medial, apresentando conceitos e teoremas a fim de construir algoritmos para a extração do eixo medial em R3. A deformação será, então, definida por movimentos locais das bolas ao longo das direções do eixo medial. Este trabalho contém resultados com movimentos simples, em um programa que utiliza a biblioteca CGAL
The medial axis is a compact description of an object that preserves its topology and naturally induces a discretisation of its forma in terms of union of balls. The study of union of balls has applications in various areas of Mathematics, in particular in Computational Geometry where it is used for curve and surface reconstruction. This work pretends to use union of balls in order to simulate deformations described on the medial axis. It introduces concepts and theorems in order to setup algorithms for medial axis extraction in R3. The deformation will thus be defined by local ball moves along the medial axis directions. This work contains results with simple movements, in a program that uses the CGAL library

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Heath, Marcus R. A. (Richard Austin). "Dynamic behavior of a three dimensional aluminum truss in free space." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/37525.

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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Ocean Engineering, 1994, and Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1994.
Includes bibliographical references (leaf 72).
by Marcus R.A. Heath.
M.S.

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Miller, Matthew Sean. "The rational homotopy types of configuration spaces of three-dimensional lens spaces /." view abstract or download file of text, 2007. http://proquest.umi.com/pqdweb?did=1417807461&sid=1&Fmt=2&clientId=11238&RQT=309&VName=PQD.

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Thesis (Ph. D.)--University of Oregon, 2007.
Typescript. Includes vita and abstract. Includes bibliographical references (leaf 76). Also available for download via the World Wide Web; free to University of Oregon users.

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Yeung, Keith Kai. "A low cost three-dimensional vision system using space-encoded spot projection." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/26346.

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Vision support plays an important role in intelligent robotic systems. It is often necessary to first recognize the location and the shape of the work piece before the robot arm can be directed to perform various tasks on it. A low cost three-dimensional (3-D) vision system based upon the space - encoded spot projection technique has been developed to measure the shape of a smooth, featureless curved surface. The vision system projects a 32x32 array of spots onto the measurement surface and uses a binary space-encoding scheme to incorporate the column address of these projection spots in a series of five projection patterns. Binary thresholding is implemented to extract the spot features in the images of the projection patterns. The image centroid positions and the decoded column addresses of the spot features, as well as the transformation matrices of the camera and slide projector are used to compute the spatial coordinates of the projection spots. This thesis establishes a calibration procedure to derive the transformation matrix of the camera using the measured spatial and image coordinates of a set of calibration image feature points. A similar calibration procedure is also established for the derivation of the transformation matrix of the slide projector. The accuracy of these matrices are substantially improved due to the utilization of the random sample consensus (RANSAC) algorithm to eliminate the gross error data points in the sample populations and allow only the good samples to be used in the derivation of the final transformation matrices. A surface reflectance model and a image centroid separation models are developed to describe the image intensity and spacings of the projection spots as a function of the measurement surface orientation. Using these models, the limiting orientations of a measurement surface with respect to the optical configuration of the vision system were found. Three reconstruction algorithms for fitting a surface to the scattered amplitude samples obtained by the spot projection system are described in the thesis. The suitability of these algorithms for the measurement of aircraft-wing surfaces is also discussed. The shape measurement results on a cylindrical surface showed that the average measurement error of points on a smooth featureless surface is less than a tenth of an inch, and the maximum error is less than a quarter of an inch in a total field of 20x20 inches.
Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate

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Lichtenstein, Antje [Verfasser], and Matthias [Akademischer Betreuer] Rötting. "Presenting Visual Information in Three-Dimensional Space / Antje Lichtenstein. Betreuer: Matthias Rötting." Berlin : Universitätsbibliothek der Technischen Universität Berlin, 2013. http://d-nb.info/1033891304/34.

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BARROSO, VITOR BARATA RIBEIRO BLANCO. "EFFICIENT FLUID SIMULATION IN THE PARAMETRIC SPACE OF THREE-DIMENSIONAL STRUCTURED GRIDS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=28689@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
BOLSA NOTA 10
Fluidos são extremamente comuns em nosso mundo e têm papel central em muitos fenômenos naturais. A compreensão de seu comportamento tem importância fundamental em uma vasta gama de aplicações e diversas áreas de pesquisa, da análise de fluxo sanguíneo até o transporte de petróleo, da exploração do fluxo de um rio até a previsão de maremotos, tempestades e furacões. Na simulação de fluidos, a abordagem conhecida como Euleriana é capaz de gerar resultados bastante corretos e precisos, mas as computações envolvidas podem se tornar excessivamente custosas quando há a necessidade de tratar fronteiras curvas e obstáculos com formas complexas. Este trabalho aborda esse problema e apresenta uma técnica Euleriana rápida e direta para simular o escoamento de fluidos em grades estruturadas parametrizadas tridimensionais. O principal objetivo do método é tratar de forma correta e eficiente as interações de fluidos com fronteiras curvas, incluindo paredes externas e obstáculos internos. Para isso, são utilizadas matrizes Jacobianas por célula para relacionar as derivadas de campos escalares e vetoriais nos espaços do mundo e paramétrico, o que permite a resolução das equações de Navier-Stokes diretamente no segundo, onde a discretização do domínio torna-se simplesmente uma grade uniforme. O trabalho parte de um simulador baseado em grades regulares e descreve como adaptá-lo com a aplicação das matrizes Jacobianas em cada passo, incluindo a resolução de equações de Poisson e dos sistemas lineares esparsos associados, utilizando tanto iterações de Jacobi quanto o método do Gradiente Biconjugado Estabilizado. A técnica é implementada na linguagem de programação CUDA e procura explorar ao máximo a arquitetura massivamente paralela das placas gráficas atuais.
Fluids are extremely common in our world and play a central role in many natural phenomena. Understanding their behavior is of great importance to a broad range of applications and several areas of research, from blood flow analysis to oil transportation, from the exploitation of river flows to the prediction of tidal waves, storms and hurricanes. When simulating fluids, the so-called Eulerian approach can generate quite correct and precise results, but the computations involved can become excessively expensive when curved boundaries and obstacles with complex shapes need to be taken into account. This work addresses this problem and presents a fast and straightforward Eulerian technique to simulate fluid flows in three-dimensional parameterized structured grids. The method s primary design goal is the correct and efficient handling of fluid interactions with curved boundary walls and internal obstacles. This is accomplished by the use of per-cell Jacobian matrices to relate field derivatives in the world and parameter spaces, which allows the Navier-Stokes equations to be solved directly in the latter, where the domain discretization becomes a simple uniform grid. The work builds on a regular-grid-based simulator and describes how to apply Jacobian matrices to each step, including the solution of Poisson equations and the related sparse linear systems using both Jacobi iterations and a Biconjugate Gradient Stabilized solver. The technique is implemented efficiently in the CUDA programming language and strives to take full advantage of the massively parallel architecture of today s graphics cards.

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Hesterberg, Stephen Gregory. "Three-dimensional Interstitial Space Mediates Predator Foraging Success in Different Spatial Arrangements." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6096.

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Habitat structure modifies the strength of predator-prey interactions, but it remains unclear how to describe the three-dimensional spatial arrangement of structural components in a way that consistently predicts outcomes. Interstitial space may provide a useful target for measurement, but most studies use only two-dimensional methods to describe 3D space, limiting their predictive power. Using a novel technology to produce identical components, this study tests whether the 3D interstitial space of oyster shell mimics modifies the ability of blue crabs (Callinectes sapidus) to capture their mud crab prey (Eurypanopeous depressus) in mesocosms and a variety of reef-associated predators to capture tethered mud crabs in the field. To accomplish this, individual interstices were manipulated by changing either the orientation or internal shape of 3D printed shell mimics, representing possible ways natural oyster shells differ spatially on a reef. In mesocosms, 3D interstitial space strongly affected prey survivorship in both spatial arrangements, but striking variation in the ability of individual blue crabs to consume their prey in the Shape 1 structures was notable. Field tethering experiments mostly corroborated mesocosm findings, except in the shell shape treatment. These unexpected results were likely an artifact of differences in predation between field experiments and highlight the specificity of predator-prey interactions in structured habitats. Together, these results demonstrate that the 3D interstitial space created from the spatial arrangement of structural components can mediate predator foraging success independent of the widely studied density attribute, but these outcomes are further dependent on both predator and prey identity as well as individual variation. This study also identifies a potential target for quantifying the spatial arrangement of structural components and proposes that such a measure should be three-dimensional, capture both the size and shape of an interstice, and scaled to the specific predator-prey interaction in question.

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Nell, Raymond D. "Three dimensional depth visualization using image sensing to detect artefact in space." Thesis, Cape Peninsula University of Technology, 2014. http://hdl.handle.net/20.500.11838/1199.

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Thesis submitted in fulfilment of the requirements for the degree Doctor of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology 2014
Three-dimensional (3D) artefact detection can provide the conception of vision and real time interaction of electronic products with devices. The orientation and interaction of electrical systems with objects can be obtained. The introduction of electronic vision detection can be used in multiple applications, from industry, in robotics and also to give orientation to humans to their immediate surroundings. An article covering holograms states that these images can provide information about an object that can be examined from different angles. The limitations of a hologram are that there must be absolute immobilization of the object and the image system. Humans are capable of stereoscopic vision where two images are fused together to provide a 3D view of an object. In this research, two digital images are used to determine the artefact position in space. The application of a camera is utilized and the 3D coordinates of the artefact are determined. To obtain the 3D position, the principles of the pinhole camera, a single lens as well as two image visualizations are applied. This study explains the method used to determine the artefact position in space. To obtain the 3D position of an artefact with a single image was derived. The mathematical formulae are derived to determine the 3D position of an artefact in space and these formulae are applied in the pinhole camera setup to determine the 3D position. The application is also applied in the X-ray spectrum, where the length of structures can be obtained using the mathematical principles derived. The XYZ coordinates are determined, a computer simulation as well as the experimental results are explained. With this 3D detection method, devices can be connected to a computer to have real time image updates and interaction of objects in an XYZ coordinate system. Keywords: 3D point, xyz-coordinates, lens, hologram

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Ausdenmoore, Benjamin D. "Synaptic contact localization in three dimensional space using a Center Distance Algorithm." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1320866829.

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Wikander, Gustav. "Three dimensional object recognition for robot conveyor picking." Thesis, Linköping University, Department of Electrical Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-18373.

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Shape-based matching (SBM) is a method for matching objects in greyscale images. It extracts edges from search images and matches them to a model using a similarity measure. In this thesis we extend SBM to find the tilt and height position of the object in addition to the z-plane rotation and x-y-position. The search is conducted using a scale pyramid to improve the search speed. A 3D matching can be done for small tilt angles by using SBM on height data and extending it with additional steps to calculate the tilt of the object. The full pose is useful for picking objects with an industrial robot.

The tilt of the object is calculated using a RANSAC plane estimator. After the 2D search the differences in height between all corresponding points of the model and the live image are calculated. By estimating a plane to this difference the tilt of the object can be calculated. Using the tilt the model edges are tilted in order to improve the matching at the next scale level.

The problems that arise with occlusion and missing data have been studied. Missing data and erroneous data have been thresholded manually after conducting tests where automatic filling of missing data did not noticeably improve the matching. The automatic filling could introduce new false edges and remove true ones, thus lowering the score.

Experiments have been conducted where objects have been placed at increasing tilt angles. The results show that the matching algorithm is object dependent and correct matches are almost always found for tilt angles less than 10 degrees. This is very similar to the original 2D SBM because the model edges does not change much for such small angels. For tilt angles up to about 25 degrees most objects can be matched and for nice objects correct matches can be done at large tilt angles of up to 40 degrees.

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Scannell, Peter. "Three-dimensional Information Space : An Exploration of a World Wide Web-based, Three-dimensional, Hierarchical Information Retrieval Interface Using Virtual Reality Modeling Language." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc278715/.

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This study examined the differences between a 3-D, VRML search interface, similar to Cone Trees, as a front-end to Yahoo on the World Wide Web and a conventional text-based, 1-Dinterface to the same database. The study sought to determine how quickly users could find information using both interfaces, their degree of satisfaction with both search interfaces, and which interface they preferred.

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Curtis, Phillip. "Frequency-domain range data registration for three-dimensional space modeling in robotic applications." Thesis, University of Ottawa (Canada), 2006. http://hdl.handle.net/10393/27120.

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The registration method presented in this thesis does not require an initial estimation of the transformation, and avoids problems of the classical iterative techniques by employing the multi-dimensional Fourier transform, which decouples the estimation of rotational parameters from the estimation of the translational parameters. Using the magnitude of the Fourier transform, an axis of rotation is estimated by determining the line that contains the minimal energy differential between two rotated 3-D images. By using a coarse to fine approach, the angle of rotation is determined from the minimal sum squared difference between the two rotated image. As the Fourier transform introduces hermitical symmetry in the rotation, the proper solution is identified through the use of a phase-correlation technique, and the estimate of translation is simultaneously obtained. Experimental results illustrate the accuracy that can be achieved by the proposed registration technique and performance is compared with that of the classical iterative closest point method.

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Ward, Charles. "Modification of a Ground Based Atomic Oxygen Simulation Apparatus to Accommodate Three Dimensional Specimens." DigitalCommons@CalPoly, 2018. https://digitalcommons.calpoly.edu/theses/1850.

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The space environment presents various challenges when designing systems and selecting materials for applications beyond Earth’s atmosphere. For mission success, these challenges must be considered. One of the detrimental aspects of the space en- vironment is Atomic Oxygen, AO. Only present in harmful quantities in Lower Earth Orbit, LEO, AO causes significant damage to materials by breaking molecular bonds. California Polytechnic State University’s, Cal Poly’s, space environments laboratory features an apparatus capable of simulating this environment. Very thin or short samples were tested to observe the mass loss due to erosion of the sample material. Recent modifications to the system allow it to expose surfaces of three dimensional objects to AO rather than only those two dimensional objects. Simulating this effect on taller samples makes available the opportunity to test coupons that are then used in additional testing to measure the effect of that erosion on other properties. Challenges in adapting the AO system are explored and addressed, as well as some possible use cases for future work. As a use case, bending moment specimens were exposed to AO prior to testing in four point bending. Multiple regression models were constructed to determine variables contributing to slope changes between specimen pairs’ linear-elastic regions of force-displacement graphs. Results show that AO exposed specimens had significantly gentler slopes in the linear elastic region of the force-displacement curve, meaning that AO exposure reduced structural rigidity of the coupons.

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Bond, Brendan. "In all directions : an investigation of multidirectional camera-centric rigs in hypothetical space /." Online version of thesis, 2008. http://hdl.handle.net/1850/7751.

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Pepper, A. "Drawing in space : a holographic system to simultaneously draw images on a flat surface and in three-dimensional space." Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.629124.

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Buchele, Suzanne Fox. "Three-dimensional binary space partitioning tree and constructive solid geometry tree construction from algebraic boundary representations /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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Lee, Chak-pui Terence. "Unified percepts in three-dimensional space derived from motion in depth or rotation in depth." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B37943741.

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Lee, Chak-pui Terence, and 李澤沛. "Unified percepts in three-dimensional space derived from motion in depth or rotation in depth." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2007. http://hub.hku.hk/bib/B37943741.

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Kowalski, Karl Gerald. "Applications of a three-dimensional position and attitude sensing system for neutral buoyancy space simulation." Thesis, Massachusetts Institute of Technology, 1990. http://hdl.handle.net/1721.1/42978.

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Qu, Zhen, and Ivan B. Djordjevic. "High-speed free-space optical continuous-variable quantum key distribution enabled by three-dimensional multiplexing." OPTICAL SOC AMER, 2017. http://hdl.handle.net/10150/623804.

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A high-speed four-state continuous-variable quantum key distribution (CV-QKD) system, enabled by wavelength-division multiplexing, polarization multiplexing, and orbital angular momentum (OAM) multiplexing, is studied in the presence of atmospheric turbulence. The atmospheric turbulence channel is emulated by two spatial light modulators (SLMs) on which two randomly generated azimuthal phase patterns yielding Andrews' spectrum are recorded. The phase noise is mitigated by the phase noise cancellation (PNC) stage, and channel transmittance can be monitored directly by the D.C. level in our PNC stage. After the system calibration, a total SKR of > 1.68 Gbit/s can be reached in the ideal system, featured with lossless channel and free of excess noise. In our experiment, based on commercial photodetectors, the minimum transmittances of 0.21 and 0.29 are required for OAM states of 2 (or -2) and 6 (or -6), respectively, to guarantee the secure transmission, while a total SKR of 120 Mbit/s can be obtained in case of mean transmittances. (C) 2016 Optical Society of America

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Hohenstein, Viviana. "The Space in between : Exploring weave knitted textiles by constructing surface patterns on three-dimensional shapes." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-12398.

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In the field of knitting, the binding weave knitting is mainly used for technical textiles, where the textiles have a high performance require- ment. Weave knit is constructed by placing an inlay thread between the knitting rows in a similar manner as a weft thread in a woven tex- tile. This work sets out to design three-dimensional weave-knitted tex- tiles in combination with intarsia and partial knit with the intention to develop surface pattern on three-dimensional shapes. The material used are effect yarn, monofilament and chenille yarn, which improve the properties of the textile. The three techniques enhance each other by their characteristics and give the possibility of formability. The re- sult shows an installation of textiles with three-dimensional character- istics, meant for spatial contexts which have the ability to function with light. The value of this work lies in the combination of the techniques and the application area in which the work is set.

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Biland, Hans Peter. "The recognition and volumetric description of three-dimensional polyhedral scenes by analysis of Hough-space structures /." Zürich, 1987. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=8289.

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Stumpf, Erika. "Neurons in cat primary auditory cortex sensitive to correlates of auditory motion in three-dimensional space." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/29640.

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The primary auditory cortex (area AI) plays an important role in the localization of static sound sources. However, little is known concerning how it processes information about sound source motion. This study was undertaken to investigate the responses of single neurons in the primary auditory cortex of the cat to correlates of auditory motion in space. Diotic and dichotic changes in sound intensity presented through earphones simulated auditory motion in four directions: toward and away from the receiver along the midline, into the ipsilateral hemifield and into the contralateral hemifield. Different rates of intensity change simulated sound source velocity. Results indicate that AI neurons can be highly selective to intensity correlates of auditory motion. Three major classes of neurons were encountered: neurons sensitive to motion toward or away from the receiver, neurons sensitive to ipsilateral- or contralateral-directed motion, and monaural-like neurons. The different classes of direction-selective neurons were spatially segregated from each other and appeared to occur in clusters or columns in the cortex. In addition to their selectivity for different directions of simulated sound source motion, AI neurons also responded selectively to the rate and excursion of intensity changes, a correlate of sound source velocity. The major determinants of direction and velocity selectivity were interactions between the following response properties of AI neurons: binaural interaction type, ear dominance, on/off responses, and monotonicity of rate/intensity function. These findings suggest that neural processing of auditory motion may involve neural mechanisms distinct from those involved in static sound localization, and indicate that some neurons in the primary auditory cortex may be part of a specialized motion-detecting mechanism in the auditory system.
Arts, Faculty of
Psychology, Department of
Graduate

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47

Wall, Charles Edward. "Numerical investigations of hyperscaling and real space renormalisation group transformations in the three dimensional Ising model." Thesis, University of Edinburgh, 1986. http://hdl.handle.net/1842/14629.

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Lind, Johan. "Make it Meaningful : Semantic Segmentation of Three-Dimensional Urban Scene Models." Thesis, Linköpings universitet, Datorseende, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-143599.

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Semantic segmentation of a scene aims to give meaning to the scene by dividing it into meaningful — semantic — parts. Understanding the scene is of great interest for all kinds of autonomous systems, but manual annotation is simply too time consuming, which is why there is a need for an alternative approach. This thesis investigates the possibility of automatically segmenting 3D-models of urban scenes, such as buildings, into a predetermined set of labels. The approach was to first acquire ground truth data by manually annotating five 3D-models of different urban scenes. The next step was to extract features from the 3D-models and evaluate which ones constitutes a suitable feature space. Finally, three supervised learners were implemented and evaluated: k-Nearest Neighbour (KNN), Support Vector Machine (SVM) and Random Classification Forest (RCF). The classifications were done point-wise, classifying each 3D-point in the dense point cloud belonging to the model being classified. The result showed that the best suitable feature space is not necessarily the one containing all features. The KNN classifier got the highest average accuracy overall models — classifying 42.5% of the 3D points correct. The RCF classifier managed to classify 66.7% points correct in one of the models, but had worse performance for the rest of the models and thus resulting in a lower average accuracy compared to KNN. In general, KNN, SVM, and RCF seemed to have different benefits and drawbacks. KNN is simple and intuitive but by far the slowest classifier when dealing with a large set of training data. SVM and RCF are both fast but difficult to tune as there are more parameters to adjust. Whether the reason for obtaining the relatively low highest accuracy was due to the lack of ground truth training data, unbalanced validation models, or the capacity of the learners, was never investigated due to a limited time span. However, this ought to be investigated in future studies.

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Shelton, Brett E. "How augmented reality helps students learn dynamic spatial relationships /." Thesis, Connect to this title online; UW restricted, 2003. http://hdl.handle.net/1773/7668.

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Skene, Gerrard. "Teaching with difference : barriers and enablers for teachers with impairments in their professional roles." Thesis, Federation University Australia, 2022. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/185861.

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Amidst the current groundswell of inclusive practices adopted in learning institutions, there would appear to be a paucity of research regarding the barriers and enablers experienced by teachers with impairments in Australian education systems (Burke, 2016; Pritchard, 2010; Sheridan & Kotevski, 2014). This thesis presents an examination of national and international literature where an imprecise range of issues for teachers with impairments is identified. The social model of disability has been adopted as the overarching theoretical perspective for this study. The conceptualisation of teaching with impairment, rather than about impairment, embodies the notion of teachers with impairments as being culturally relevant educators (Pritchard, 2010). Narrative inquiry, in conjunction with Clandinin and Connelly’s (2000) three-dimensional space approach as a thematical analysis methodology, has been employed and supports the investigation of ten teachers with impairments working in professional education roles within Australia. Narrative interviews were conducted with each of the ten participants with the aim of identifying barriers and enablers within the lived experiences of teachers with impairments. This study identified a silence in relation to teachers with impairments, and to address this silence has amplified the voices of teachers with impairments. Five primary themes emerged from the data to provide insights into barriers and enablers experienced by teachers with impairments. These themes are: Thinking about becoming a teacher; The limiting attitudes of others; Connecting with students and parents; Notions of teaching spaces; and I get by with a little help from my friends. This study found that teachers with impairments do experience adverse attitudes and biases in Australian teaching institutions despite there being laws that have been specifically designed to prevent disability discrimination. Bias, experienced as discrimination towards teachers with impairments, extends to career promotion and workplace advancement opportunities. Conversely, the study also found that respectful conversations about impairment which took place both inside and outside teaching places, highlighted how having open conversations about reasonable adjustments can lead to actions that become enablers for teachers with impairments. This study commences the important work of giving voice to teachers with impairments and creates a space to challenge dominant perspectives. The thesis concludes that more needs to be done to challenge the constructed normative attitudes that are responsible for setting teachers with impairments apart and resulting in them being mostly undetected within the teacher population; Doctor of Philosophy

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Dissertations / Theses on the topic 'Three dimensional space'

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