33 resultados para Three Dimensional Graphics and Realism


Relevância:

100.00% 100.00%

Publicador:

Resumo:

Determining the foraging behaviour of free-ranging marine animals is fundamental for assessing their habitat use and how they may respond to changes in the environment. However, despite recent advances in bio-logging technology, collecting information on both at-sea movement patterns and activity budgets still remains difficult in small pelagic seabird species due to the constraints of instrument size. The short-tailed shearwater, the most abundant seabird species in Australia (ca 23 million individuals), is a highly pelagic procellariiform. Despite its ecological importance to the region, almost nothing is known about its at-sea behaviour, in particular, its foraging activity. Using a combination of GPS and tri-axial accelerometer data-loggers, the fine scale three-dimensional foraging behaviour of 10 breeding individuals from two colonies was investigated. Five at-sea behaviours were identified: (1) resting on water, (2) flapping flight, (3) gliding flight, (4) foraging (i.e., surface foraging and diving events), and (5) taking-off. There were substantial intra- and inter- individual variations in activity patterns, with individuals spending on average 45.8% (range: 17.1-70.0%) of time at sea resting on water and 18.2% (range: 2.3-49.6%) foraging. Individuals made 76.4 ± 65.3 dives (range: 8-237) per foraging trip (mean duration 9.0 ± 1.9 s), with dives also recorded during night-time. With the continued miniaturisation of recording devices, the use of combined data-loggers could provide us with further insights into the foraging behaviour of small procellariiforms, helping to better understand interactions with their prey.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This research has developed a novel 3D particle based cell model that is able to accurately estimate the membrane deformation and indentation force in bio-micromanipulation of an individual cell, especially embryos microinjection practice.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Three-dimensional (3D) printers are now commonplace in both primary and secondary schools within Australia. As with most new technologies they present a range of challenges to users in terms of technical problems and support, and how to integrate their use into the curriculum in a meaningful way. This research reports on data from a small number of Victorian primary schools from urban and regional areas. A case study methodology has been used to examine how each setting has approached the use of these printers and includes a review of the literature concerning the uptake of new technologies by non-experts. Data include interview transcripts from teachers, principals and technicians and photographic artefacts of 3D printed objects. Teachers reflected on their reasoning behind lesson plans and their aspirations for future use of 3D printers in the classroom. Some of the issues identified were teacher confidence, time to ‘play’ with and become familiar with 3D printers; and technical challenges that arose such as the time taken to print an object and clogging of printer extruders (heads). Recommendations are made concerning possible ways forward.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Complex multiphase microstructures were obtained in transformation induced plasticity C–Mn–Si–(Nb–Al–Mo) steels by simulated controlled thermomechanical processing. These microstructures were characterized using transmission electron microscopy, X-ray diffraction and three-dimensional atom probe tomography (APT), which was used to determine the partitioning of elements between different phases and microconstituents. The measured carbon concentration (not, vert, similar0.25 at%) in the ferrite of carbide-free bainite was higher than expected from para-equilibrium between the austenite and ferrite, while the concentrations of substitutional elements were the same as in the parent austenite suggesting that incomplete bainite transformation occurred. In contrast, the distribution of substitutional elements between the ferrite lath and austenite in carbide-containing bainite indicated a complete bainite reaction. The average carbon content in the retained austenite (3.2 ± 1.6 at%) was somewhat higher than the T0 limit. On the basis of the APT measured composition, the calculated Ms temperatures for retained austenite were above room temperature, indicating its low chemical stability.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Laser shock peening (LSP) is an innovative surface treatment technique for metal alloys, with the great improvement of their fatigue, corrosion and wear resistance performance. Finite element method has been widely applied to simulate the LSP to provide the theoretically predictive assessment and optimally parametric design. In the current work, 3-D numerical modelling approaches, combining the explicit dynamic analysis, static equilibrium analysis algorithms and different plasticity models for the high strain rate exceeding 106s-1, are further developed. To verify the proposed methods, 3-D static and dynamic FEA of AA7075-T7351 rods subject to two-sided laser shock peening are performed using the FEA package–ABAQUS. The dynamic and residual stress fields, shock wave propagation and surface deformation of the treated metal from different material modelling approaches have a good agreement.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Three-dimensional virtual environments (3dves) are the new generation of digital multi-user social networking platforms. Their immersive character allows users to create a digital humanised representation or avatar, enabling a degree of virtual interaction not possible through conventional text-based internet technologies. As recent international experience demonstrates, in addition to the conventional range of cybercrimes (including economic fraud, the dissemination of child pornography and copyright violations), the 'virtual-reality' promoted by 3dves is the source of great speculation and concern over a range of specific and emerging forms of crime and harm to users. This paper provides some examples of the types of harm currently emerging in 3dves and suggests internal regulation by user groups, terms of service, or end-user licensing agreements, possibly linked to real-world criminological principles. This paper also provides some directions for future research aimed at understanding the role of Australian criminal law and the justice system more broadly in this emerging field.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This thesis investigates three-dimensional porous polymer blend scaffolds fabricated using supercritical carbon dioxide combined with solvent etching. These scaffolds with improved pore structures and interconnectivity can be used in regeneration medicine and tissue engineering application.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In this article, we report on the preparation and cell culture performance of a novel fibrous matrix that has an interbonded fiber architecture, excellent pore interconnectivity, and controlled pore size and porosity. The fibrous matrices were prepared by combining melt-bonding of short synthetic fibers with a template leaching technique. The microcomputed tomography and scanning electron microscopy imaging verified that the fibers in the matrix were highly bonded, forming unique isotropic pore architectures. The average pore size and porosity of the fibrous matrices were controlled by the fiber/template ratio. The matrices having the average pore size of 120, 207, 813, and 994 mm, with the respective porosity of 73%, 88%, 96%, and 97%, were investigated. The applicability of the matrix as a three-dimensional (3D) tissue scaffold for cell culture was demonstrated with two cell lines, rat skin fibroblast and Chinese hamster ovary, and the influences of the matrix porosity and surface area on the cell culture performance were examined. Both cell lines grew successfully in the matrices, but they showed different preferences in pore size and porosity. Compared with two-dimensional tissue culture plates, the cell number on 3D fibrous matrices was increased by 97.27% for the Chinese hamster ovary cells and 49.46% for the fibroblasts after 21 days of culture. The fibroblasts in the matrices not only grew along the fiber surface but also bridged among the fibers, which was much different from those on two-dimensional scaffolds. Such an interbonded fibrous matrix may be useful for developing new fiber-based 3D tissue scaffolds for various cell culture applications.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

This paper uses finite element upper and lower bound limit analysis to produce chart solutions for three-dimensional (3D) natural slopes for both short- and long-term stability. The presented chart solutions are convenient tools that can be used for preliminary design purposes. The rigorous limit analysis results in this paper were found to bracket the true factor of safety within ±10% or better, which can be used as a benchmark for the solutions from other methods. The depth of the slip surfaces is observed to be generally shallow for most analyzed cases, particularly for the long-term slope stability problem. In addition, it was found that using a two-dimensional (2D) analysis may lead to significant differences in estimating safety factors, which can differ by 2%–60% depending on the slope geometry and soil properties. Therefore, great care and judgement are required when applying 2D analyses to 3D slope problems.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Multilobal fibres are irregularly shaped fibres with several surface channels or grooves. Scaffolds created from these fibres have high surface area which may enhance cell density. This study compared the cell growth of dermal fibroblasts and osteoblast-like SaOS2 cells on multilobal fibre nonwoven scaffolds to the conventional fibre scaffolds. Cells were cultured on round nylon, trilobal nylon, round polyethylene terephthalate (PET) and multilobal PET scaffolds for 14 days. There were more cells growing on trilobal nylon and PET multilobal scaffolds than their round counterparts. The preference to the type of multilobal scaffolds was cell dependent. The density of fibroblast increased 37% on trilobal nylon compared to round nylon scaffolds after 14 days of culture. SaOS2 cells preferred the multilobal PET scaffolds, exhibiting a 66% increase in cell number after 14 days of culture. Scaffolds manufactured from multilobal fibres have the ability to accommodate a high number of cells, demonstrating a great potential in tissue engineering applications.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Getting intimate: A 3D interconnected Bi0.5Sr 0.5FeO3-ð (BSF)-Ag electrocatalyst is prepared from a BSF-AgNO3 core-shell precursor in one step. The nanometer-sized Ag enhances the sintering process, enabling an optimum cathode microstructure and good cathode-to-electrolyte attachment upon firing at 850°C. A solid-oxide fuel cell based on this cathode shows a near 100% peak power density enhancement at 550°C.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Purpose : This study tests the hypothesis that 3-dimensional computed tomography (CT) reconstructions improve interobserver agreement on classification and treatment of coronoid fractures compared with 2-dimensional CT.

Methods : A total of 29 orthopedic surgeons evaluated 10 coronoid fractures on 2 occasions (first with radiographs and 2-dimensional CT and then with radiographs and 3-dimensional CT), separated by a minimum of 2 weeks. Surgeons classified fractures according to the classifications of Regan and Morrey and of O'Driscoll et al., identified specific characteristics, recommended the most appropriate treatment approach, and made treatment recommendations. The kappa multirater measure (κ) was calculated to estimate agreement between observers.

Results : Regardless of the imaging modality used, there was fair to moderate agreement for most of the observations. Three-dimensional CT improved interobserver agreement in Regan and Morrey's classsication (κ3-dimensional = 0.51 vs κ2-dimensional = 0.40; p < .001) and O'Driscoll et al.'s classifications (κ3-dimensional = 0.48 vs κ2-dimensional = 0.42; p = .009). There were trends toward better reliability for 3-dimensional reconstruction in recognition of coronoid tip fractures (κ3-dimensional = 0.19, κ2-dimensional = 0.03; p = .268), comminution (κ3-dimensional = 0.41 vs κ2-dimensional = 0.29; p = .133), and impacted fragments (κ3-dimensional = 0.39 vs κ2-dimensional = 0.27; p = .094), and in surgeons' opinions on the need for something other than screws or plate for surgical fixation (κ3-dimensional = 0.31 vs κ2-dimensional = 0.15; p = .138). Interobserver agreement on treatment approach was better with 2-dimensional CT (κ3-dimensional = 0.27, κ2-dimensional = 0.32; p = .015).

Conclusions :
Three-dimensional CT reconstructions improve interobserver agreement with respect to fracture classification compared with 2-dimensional CT.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Atherosclerosis is a progressive disease, involving the build-up of lipid streaks in artery walls, leading to plaques. Understanding the development of atherosclerosis and plaque vulnerability is critically important since plaque rupture can result in heart attack or stroke. Plaques can be divided into two distinct types: those likely to rupture (vulnerable) or less likely to rupture (stable). In the last decade, researchers have been interested in studying the influence of the mechanical effects (blood shear stress, pressure forces and structural stress) on the plaque formation, progression and rupture processes but no general agreement has been found. The purpose of the present work is to include more realistic conditions for the numerical calculations of the blood flow by implementing real geometries with plaques in the numerical model. Hemodynamical parameters are studied in both diseased and healthy configurations. The healthy configuration is obtained by removing numerically the plaques from three dimensional geometries obtained by micro-computed tomography. A new hemodynamical parameter is also introduced to relate the location of plaques to the characteristics of the flow in the healthy configuration. © 2014 .

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Electrically conductive graphene-filled polystyrene nanocomposites with well-organized three dimensional (3D) microstructures were simply prepared by electrostatic assembly integrated latex technology. First, positively charged polystyrene was synthesized via disperse polymerization in ethanol/water medium by using a cationic co-monomer, and then directly co-assembled with graphene oxide. Eventually, a honeycomb-like graphene 3D framework was embedded in polystyrene matrix after in situ chemical reduction and hot compression molding. Due to the 3D conductive pathway derived from graphene based network evidenced by morphology studies, the fabricated nanocomposites show excellent electrical properties, i.e. extremely low percolation threshold of 0.09 vol% and high saturated conductivity of 25.2 S/m at GNs content of 1.22 vol%. © 2014 Elsevier B.V.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Nanomaterials are rich in potential, particularly for the formation of scaffolds that mimic the landscape of the host environment of the cell. This niche arises from the spatial organization of a series of biochemical and biomechanical signals. Self-assembling peptides have emerged as an important tool in the development of functional (bio-)nanomaterials; these simple, easily synthesized subunits form structures which present the properties of these larger, more complex systems. Scaffolds based upon these nanofibrous matrices are promising materials for regenerative medicine as part of a new methodology in scaffold design where a "bottom-up" approach is used in order to simulate the native cellular milieu. Importantly, SAPs hold the potential to be bioactive through the presentation of biochemical and biomechanical signals in a context similar to the natural extracellular matrix, making them ideal targets for providing structural and chemical support in a cellular context. Here, we discuss a new methodology for the presentation of biologically relevant epitopes through their effective presentation on the surface of the nanofibers. Here, we demonstrate that these signals have a direct effect on the viability of cells within a three-dimensional matrix as compared with an unfunctionalized, yet mechanically and morphologically similar system. © 2014 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 102: 197-205, 2014.