Creating harmonious and legible colour schemes in the automated generation of multimedia presentations

Due to the growing amount of information on the web, the user specific requirements and different characteristics of output devices, the opportunities for the automatic generation of multimedia presentations grow. The multimedia presentation generator, that resides in a dynamic environment, such as a museum website, where the user requirements, presentation device characteristics, presentation content and the domain characteristics are not known in advance, needs to be able to compose a presentation. With respect to stylistic design, graphic designers can create a template providing stylistic aspects, but as soon as any of the dynamic attributes of the system change this can result in the need for redesign. We argue that with the correct balance between form and function and by using relevant aspects of design theory, the automatic presentation generator can keep harmony and legibility factors in balance. The aim of this work is to demonstrate this approach on the example of automatic colour design with the use of colour theory from Itten and Tufte. By taking required legibility factors into account, harmonious and well balanced colour schemes, adapted to the requirements of the user, the characteristics of the presentation platform, the content's domain and discourse model can be created. We apply our approach to the domain of presentation environments for musea for fine arts

Vessel Axis Tracking Using Topology Constrained Surface Evolution

An approach to three-dimensional vessel axis tracking based on surface evolution is presented. The main idea is to guide the evolution of the surface by analyzing its skeleton topology during evolution, and imposing shape constraints on the topology. For example, the intermediate topology can be processed such that it represents a single vessel segment, a bifurcation, or a more complex vascular topology. The evolving surface is then re-initialized with the newly found topology. Re-initialization is a crucial step since it creates probing behavior of the evolving front, encourages the segmentation process to extract the vascular structure of interest and reduces the risk on leaking of the curve into the background. The method was evaluated in two computed tomography angiography applications: (i) extracting the internal carotid arteries including the region in which they traverse through the skull base, which is challenging due to the proximity of bone structures and overlap in intensity values, and (ii) extracting the carotid bifurcations including many cases in which they are severely stenosed and contain calcifications. The vessel axis was found in 90% (18/20 internal carotids in ten patients) and 70% (14/20 carotid bifurcations in a different set of ten patients) of the cases

Vessel enhancing diffusion: a scale space representation of vessel

A method is proposed to enhance vascular structures within the framework of scale space theory. We combine a smooth vessel filter which is based on a geometrical analysis of the Hessian's eigensystem, with a non-linear anisotropic diffusion scheme. The amount and orientation of diffusion depend on the local vessel likeliness. Vessel enhancing diffusion (VED) is applied to patient and phantom data and compared to linear, regularized Perona-Malik, edge and coherence enhancing diffusion. The method performs better than most of the existing techniques in visualizing vessels with varying radii and in enhancing vessel appearance. A diameter study on phantom data shows that VED least affects the accuracy of diameter measurements. It is shown that using VED as a preprocessing step improves level set based segmentation of the cerebral vasculature, in particular segmentation of the smaller vessels of the vasculature

Robust semi-automated path extraction for visualising stenosis of the coronary arteries

Computed tomography angiography (CTA) is useful for diagnosing and planning treatment of heart disease. However, contrast agent in surrounding structures (such as the aorta and left ventricle) makes 3-D visualisation of the coronary arteries difficult. This paper presents a composite method employing segmentation and volume rendering to overcome this issue. A key contribution is a novel Fast Marching minimal path cost function for vessel centreline extraction. The resultant centreline is used to compute a measure of vessel lumen, which indicates the degree of stenosis (narrowing of a vessel). Two volume visualisation techniques are presented which utilise the segmented arteries and lumen measure. The system is evaluated and demonstrated using synthetic and clinically obtained datasets

Calendar 2001

The annual University publication which provides general and historical information about the University of Sydney, the statutes and regulations under which it operates and the Senate resolutions relating to constitutions and courses in each faculty

30 Yan-nhanu language documentation and revitalisation

Breastfeeding may have a protective effect on the development of obesity in later life. Not much is known about the effects of infant feeding on more-specific fat measures.We examined associations of breastfeeding duration and exclusiveness and age at the introduction of solid foods with general and abdominal fat outcomes in children.We performed a population-based, prospective cohort study in 5063 children. Information about infant feeding was obtained by using questionnaires. At the median age of 6.0 y (90\% range: 5.7\%, 6.8\%), we measured childhood anthropometric measures, total fat mass and the android:gynoid fat ratio by using dual-energy X-ray absorptiometry and preperitoneal abdominal fat by using ultrasound.We observed that, in the models adjusted for child age, sex, and height only, a shorter breastfeeding duration, nonexclusive breastfeeding, and younger age at the introduction of solid foods were associated with higher childhood general and abdominal fat measures (P-trend < 0.05) but not with higher childhood body mass index. The introduction of solid foods at a younger age but not breastfeeding duration or exclusivity was associated with higher risk of overweight or obesity (OR: 2.05; 95\% CI: 1.41, 2.90). After adjustment for family-based sociodemographic, maternal lifestyle, and childhood factors, the introduction of solid food between 4-4.9 mo of age was associated with higher risks of overweight or obesity, but the overall trend was not significant.Associations of infant breastfeeding and age at the introduction of solid foods with general and abdominal fat outcomes are explained by sociodemographic and lifestyle-related factors. Whether infant dietary composition affects specific fat outcomes at older ages should be further studied

Model generation of coronary artery bifurcations from CTA and single plane angiography

International audiencePurpose: To generate accurate and realistic models of coronary artery bifurcations before and after percutaneous coronary intervention (PCI), using information from two image modalities. Because bifurcations are regions where atherosclerotic plaque appears frequently and intervention is more challenging, generation of such realistic models could be of high value to predict the risk of restenosis or thrombosis after stent implantation, and to study geometrical and hemodynamical changes. Methods: Two image modalities have been employed to generate the bifurcation models: computer tomography angiography (CTA) to obtain the 3D trajectory of vessels, and 2D conventional coronary angiography (CCA) to obtain radius information of the vessel lumen, due to its better contrast and image resolution. In addition, CCA can be acquired right before and after the intervention in the operation room; therefore, the combination of CTA and CCA allows the generation of realistic prepro-cedure and postprocedure models of coronary bifurcations. The method proposed is semiautomatic, based on landmarks manually placed on both image modalities. Results: A comparative study of the models obtained with the proposed method with models manually obtained using only CTA, shows more reliable results when both modalities are used together. The authors show that using preprocedure CTA and postprocedure CCA, realistic postprocedure models can be obtained. Analysis carried out of the Murray's law in all patient bifurcations shows the geometric improvement of PCI in our models, better than using manual models from CTA alone. An experiment using a cardiac phantom also shows the feasibility of the proposed method. Conclusions: The authors have shown that fusion of CTA and CCA is feasible for realistic generation of coronary bifurcation models before and after PCI. The method proposed is efficient, and relies on minimal user interaction, and therefore is of high value to study geometric and hemo-dynamic changes of treated patients