3D EVALUATION OF THE TOPOGRAPHY OF THE SURFACE BY ABRASIVE WATER JET MACHINING TECHNOLOGY

The article deals with contact and non-contact evaluation of surface roughness created by water jet cutting technology (AWJ). Non-contact surface measurement was performed using an LPM laser profilometer. The values measured by the laser profilometry method were compared with the values measured by the contact method, the Mitutoyo SJ 400 roughness meter. Six samples were produced. Three in stainless steel and three in structural steel. In order to achieve a different surface topography, different feed rates of the cutting head were used on the samples, which was reflected in the quality of the resulting surface. The evaluated parameters were the average arithmetic deviation of the assessed profile and the largest height of the profile inequality.

Fully automatic brain tumor segmentation for 3D evaluation in augmented reality

OBJECTIVE For currently available augmented reality workflows, 3D models need to be created with manual or semiautomatic segmentation, which is a time-consuming process. The authors created an automatic segmentation algorithm that generates 3D models of skin, brain, ventricles, and contrast-enhancing tumor from a single T1-weighted MR sequence and embedded this model into an automatic workflow for 3D evaluation of anatomical structures with augmented reality in a cloud environment. In this study, the authors validate the accuracy and efficiency of this automatic segmentation algorithm for brain tumors and compared it with a manually segmented ground truth set. METHODS Fifty contrast-enhanced T1-weighted sequences of patients with contrast-enhancing lesions measuring at least 5 cm3 were included. All slices of the ground truth set were manually segmented. The same scans were subsequently run in the cloud environment for automatic segmentation. Segmentation times were recorded. The accuracy of the algorithm was compared with that of manual segmentation and evaluated in terms of Sørensen-Dice similarity coefficient (DSC), average symmetric surface distance (ASSD), and 95th percentile of Hausdorff distance (HD95). RESULTS The mean ± SD computation time of the automatic segmentation algorithm was 753 ± 128 seconds. The mean ± SD DSC was 0.868 ± 0.07, ASSD was 1.31 ± 0.63 mm, and HD95 was 4.80 ± 3.18 mm. Meningioma (mean 0.89 and median 0.92) showed greater DSC than metastasis (mean 0.84 and median 0.85). Automatic segmentation had greater accuracy for measuring DSC (mean 0.86 and median 0.87) and HD95 (mean 3.62 mm and median 3.11 mm) of supratentorial metastasis than those of infratentorial metastasis (mean 0.82 and median 0.81 for DSC; mean 5.26 mm and median 4.72 mm for HD95). CONCLUSIONS The automatic cloud-based segmentation algorithm is reliable, accurate, and fast enough to aid neurosurgeons in everyday clinical practice by providing 3D augmented reality visualization of contrast-enhancing intracranial lesions measuring at least 5 cm3. The next steps involve incorporation of other sequences and improving accuracy with 3D fine-tuning in order to expand the scope of augmented reality workflow.

Three-dimensional non-destructive visualization of teeth enamel microcracks using X-ray micro-computed tomography

Although the topic of tooth fractures has been extensively analyzed in the dental literature, there is still insufficient information about the potential effect of enamel microcracks (EMCs) on the underlying tooth structures. For a precise examination of the extent of the damage to the tooth structure in the area of EMCs, it is necessary to carry out their volumetric [(three-dimensional (3D)] evaluation. The aim of this study was to validate an X-ray micro-computed tomography ($$\mu $$ μ CT) as a technique suitable for 3D non-destructive visualization and qualitative analysis of teeth EMCs of different severity. Extracted human maxillary premolars were examined using a $$\mu $$ μ CT instrument ZEISS Xradia 520 Versa. In order to separate crack, dentin, and enamel volumes a Deep Learning (DL) algorithm, part of the Dragonfly’s segmentation toolkit, was utilized. For segmentation needs we implemented Dragonfly’s pre-built UNet neural network. The scanning technique which was used made it possible to recognize and detect not only EMCs that are visible on the outer surface but also those that are buried deep inside the tooth. The 3D visualization, combined with DL assisted segmentation, enabled the evaluation of the dynamics of an EMC and precise examination of its position with respect to the dentin-enamel junction.

Comparison of post-operative three-dimensional and two-dimensional evaluation of component position for total knee arthroplasty

Purpose The purpose of this study was to evaluate the post-operative three-dimensional (3D) femoral and tibial component positions in total knee arthroplasty (TKA) by the same co-ordinates’ system as for pre-operative planning and to compare it with a two-dimensional (2D) evaluation. Materials and methods Sixty-five primary TKAs due to osteoarthritis were included. A computed tomography (CT) scan of the femur and tibia was obtained and pre-operative 3D planning was performed. Then, 3D and 2D post-operative evaluations of the component positions were performed. KneeCAS (LEXI, Inc., Tokyo, Japan), a lower-extremity alignment assessment system, was used for the 3D post-operative evaluation. Standard short-knee radiographs were used for the 2D post-operative evaluation. Differences between the pre-operative planning and post-operative coronal and sagittal alignment of components were investigated and compared with the results of the 3D and 2D evaluations. Results According to the 3D evaluation, the difference between the pre-operative planning and actual post-operative sagittal alignment of the femoral component and the coronal and sagittal alignments of the tibial component were 2.6° ± 1.8°, 2.2° ± 1.8° and 3.2° ± 2.4°, respectively. Using the 2D evaluation, they were 1.9° ± 1.5°, 1.3° ± 1.2° and 1.8° ± 1.4°, making the difference in 3D evaluation significantly higher (p = 0.013, = 0.003 and < 0.001). For the sagittal alignment of the femoral component and the coronal and sagittal alignment of the tibial component, the outlier (> ± 3°) ratio for the 3D evaluation was also significantly higher than that of the 2D evaluation (p < 0.001, = 0.009 and < 0.001). Conclusions The difference between the pre-operative planning and post-operative component alignment in the 3D evaluation is significantly higher than that of the 2D, even if the same cases have been evaluated. Two-dimensional evaluation may mask or underestimate the post-operative implant malposition. Three-dimensional evaluation using the same co-ordinates’ system as for pre-operative planning is necessary to accurately evaluate the post-operative component position.

3D EVALUATION OF BUSINESSES IN TERMS OF SUSTAINABLE DEVELOPMENT PURPOSES; DESCRIPTION OF THE IMPORTANCE OF SUSTAINABLE ENTREPRENEURSHIP IN THE FUTURE OF BUSINESS

Evaluation and comparison of businesses in various industrial, service, and agricultural clusters is a suitable way for determining the equivalence of their position in relation to each other if the evaluation tool can generalize and deploy in various ranges. In terms of diligence of firms and businesses trying to help the occurrence of sustainable development purposes, it is necessary to have a standard and simple tool that can be realized and used by commercial firms easily. The current article, using a qualitative method and investigating the documents and substantive concepts and open and in-depth interviews, has provided a tool for evaluation and comparison of businesses and organizations from the perspective of three dimensions of sustainable development. Services or agriculture has become easily possible, moreover due to the generalizability of its tools and items by being based on standard business literature, the ability to compare businesses in an out-cluster way has been provided, and this helps policymakers to understand the current situation and examine the desired cluster to cluster and larger which accordingly, the comparison of businesses within any industrial or service or agricultural cluster are easily possible moreover due to the generalizability of their tools and items the ability to compare out-cluster businesses is provided due to the establishment on standard business literature too. Such an issue helps policymakers survey the current and desired situation in a cluster to cluster and macro-ones. Moreover, the research findings indicate that future businesses and the future of companies depend on changing the paradigm to sustainable entrepreneurship.

Three-dimensional echocardiography

Despite the fact that three-dimensional echocardiography (3DE) has been available for many years, its utilization on a routine clinical basis has been rather limited. However, recent improvements in image quality, semi-automated quantification, better workflow, and other developments such as fusion imaging, have now accelerated the integration of 3D imaging into routine echo practice. In this chapter, we have reviewed the standard and well established applications of the technique such as volumetric chamber analysis and 3D evaluation of valvular pathology, as well as highlighting some of the exciting new developments such as the use of artificial intelligence and photo-realistic visualization. these newer techniques will undoubtedly help ensure that 3D echocardiography plays a pivotal role in contemporary cardiac imaging leading and cutting edge patient care.