IntroductionThe aim of this study was to assess if the complex anatomy of aortic aneurysm and aortic dissection can be accurately reproduced from a contrast‐enhanced computed tomography (CT) scan into a three‐dimensional (3D) printed model.MethodsContrast‐enhanced cardiac CT scans from two patients were post‐processed and produced as 3D printed thoracic aorta models of aortic aneurysm and aortic dissection. The transverse diameter was measured at five anatomical landmarks for both models, compared across three stages: the original contrast‐enhanced CT images, the stereolithography (STL) format computerised model prepared for 3D printing and the contrast‐enhanced CT of the 3D printed model. For the model with aortic dissection, measurements of the true and false lumen were taken and compared at two points on the descending aorta.ResultsThree‐dimensional printed models were generated with strong and flexible plastic material with successful replication of anatomical details of aortic structures and pathologies. The mean difference in transverse vessel diameter between the contrast‐enhanced CT images before and after 3D printing was 1.0 and 1.2 mm, for the first and second models respectively (standard deviation: 1.0 mm and 0.9 mm). Additionally, for the second model, the mean luminal diameter difference between the 3D printed model and CT images was 0.5 mm.ConclusionEncouraging results were achieved with regards to reproducing 3D models depicting aortic aneurysm and aortic dissection. Variances in vessel diameter measurement outside a standard deviation of 1 mm tolerance indicate further work is required into the assessment and accuracy of 3D model reproduction.

No abstract

No abstract

[1] X-ray microtomography (micro-CT) with micron resolution enables new ways of characterizing microstructures and opens pathways for forward calculations of multiscale rock properties. A quantitative characterization of the microstructure is the first step in this challenge. We developed a new approach to extract scale-dependent characteristics of porosity, percolation, and anisotropic permeability from 3-D microstructural models of rocks. The Hoshen-Kopelman algorithm of percolation theory is employed for a standard percolation analysis. The anisotropy of permeability is calculated by means of the star volume distribution approach. The local porosity distribution and local percolation probability are obtained by using the local porosity theory. Additionally, the local anisotropy distribution is defined and analyzed through two empirical probability density functions, the isotropy index and the elongation index. For such a high-resolution data set, the typical data sizes of the CT images are on the order of gigabytes to tens of gigabytes; thus an extremely large number of calculations are required. To resolve this large memory problem parallelization in OpenMP was used to optimally harness the shared memory infrastructure on G 3

Twenty-first-century mining is a complex pursuit. Stakeholders must manage many interconnected processes and data sets to ensure an operation is sustainable. Mixed Reality (MR) simulation may present an opportunity to improve knowledge and understanding of mine operations via a digital twin. Current and future personnel can model and make predictions using past, current and future data sets. However, MR is still an uncommon tool in the mining industry. This paper asks why that is the case, what some common barriers may be to MR adoption, and presents a possible collaborative solution to make MR sustainable as the technology gains hold and becomes commonplace in mine operations and elsewhere.

This is the second paper of a series authored by a collaboration of international researchers. It develops taxonomy for computer-based virtual reality simulators of relevance to the mining industry. A summary is presented of simulator types implemented in the industry, and continuums are used to explain concepts and issues that affect simulator development and integration. The paper classifies simulators and demonstrates that there are potentially many simulator formats still to be realised and implemented by the mining industry. Simulator issues that are often overlooked such as human factors, cognitive load and development costs and their impact on the development of sustainable simulator technologies are considered in some detail. Barriers to development and integration are mentioned, and the need for industry to engage with university-level research and develop a uniform and integrated approach are discussed. Finally, a brief case study is presented and conclusions are drawn about the current status and sustainability of simulator development in the mining industry.

No abstract

Background: 3D printing has shown great promise in medical applications, with increasing reports in liver diseases. However, research on 3D printing in biliary disease is limited with lack of studies on validation of model accuracy. In this study, we presented our experience of creating a realistic 3D printed model of biliary ducts with congenital cyst. Measurements of anatomical landmarks were compared at different stages of model generation to determine dimensional accuracy. Methods: Contrast-enhanced computed tomography (CT) images of a patient diagnosed with congenital cyst in the common bile duct with dilated hepatic ducts were used to create the 3D printed model. The 3D printed model was scanned on a 64-slice CT scanner using the similar abdominal CT protocol. Measurements of anatomical structures including common hepatic duct (CHD), right hepatic duct (RHD), left hepatic duct (LHD) and the cyst at left to right and anterior to posterior dimensions were performed and compared between original CT images, the standard tessellation language (STL) image and CT images of the 3D model. Results: The 3D printing model was successfully generated with replication of biliary ducts and cyst. Significant differences in measurements of these landmarks were found between the STL and the original CT images, and the CT images of the 3D printed model and the original CT images (P<0.05). Measurements of the RHD and LHD diameters from the original CT images were significantly larger than those from the CT images of 3D model or STL file (P<0.05), while measurements of the CHD diameters were significantly smaller than those of the other two datasets (P<0.05). No significant differences were reached in measurements of the CHD, RHD, LHD and the biliary cyst between CT images of the 3D printed model and STL file (P=0.08-0.98). Conclusions: This study shows our experience in producing a realistic 3D printed model of biliary ducts and biliary cyst. The model was found to replicate anatomical structures and cyst with high accuracy between the STL file and the CT images of the 3D model. Large discrepancy in dimensional measurements was noted between the original CT and STL file images, and the original CT and CT images of the 3D model, highlighting the necessity of further research with inclusion of more cases of biliary disease to validate accuracy of 3D printed biliary models.