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Engineering simulations have opened several gates for today's chemical engineers. They are powerful tools to provide technical content as physics-based numerical solvers. Augmented reality (AR) and virtual reality (VR), on the other hand, are already underway to digitize environments in many fields. The combination of AR/VR environments and simulations in engineering education has been attracting widespread interest. Literature has demonstrated a massive amount of educational digital environments in several contexts as being complementary to conventional educational methods. Nevertheless, hosting technical content produced by engineering simulations with educational AR/VR is still challenging and requires expertise from multiple disciplines throughout the technical development. Present work provides a facile and agile methodology for low-cost hardware but content-wise rich AR software development. A case study is developed to teach chemical-engineering concepts using a liquid-soap synthesis process. Accordingly, we assess and conclude the digital development process to guide unexperienced developers for the digitalization of teaching content. The present contribution serves as an example of the power of integrating AR/VR with traditional engineering simulations for educational purposes. The digital tool developed in this work is shared in the online version.

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Several clinical settings could benefit from 3-D high frame rate (HFR) imaging and, in particular, HFR 3-D tissue Doppler imaging (TDI). To date, the proposed methodologies are based mostly on experimental ultrasound platforms, making their translation to clinical systems nontrivial as these have additional hardware constraints. In particular, clinically used 2-D matrix array transducers rely on subaperture (SAP) beamforming to limit cabling between the ultrasound probe and the back-end console. Therefore, this paper is aimed at assessing the feasibility of HFR 3-D TDI using diverging waves (DWs) on a clinical transducer with SAP beamforming limitations. Simulation studies showed that the combination of a single DW transmission with SAP beamforming results in severe imaging artifacts due to grating lobes and reduced penetration. Interestingly, a promising tradeoff between image quality and frame rate was achieved for scan sequences with a moderate number of transmit beams. In particular, a sparse sequence with nine transmissions showed good imaging performance for an imaging sector of 70 ×70 at volume rates of approximately 600 Hz. Subsequently, this sequence was implemented in a clinical system and TDI was recorded in vivo on healthy subjects. Velocity curves were extracted and compared against conventional TDI (i.e., with focused transmit beams). The results showed similar velocities between both beamforming approaches, with a cross-correlation of 0.90 ± 0.11 between the traces of each mode. Overall, this paper indicates that HFR 3-D TDI is feasible in systems with clinical 2-D matrix arrays, despite the limitations of SAP beamforming.

It was previously demonstrated in 2-D echocardiography that a proper multiline transmit (MLT) implementation can be used to increase frame rate while preserving image quality. Initial findings for extending MLT to 3-D showed that it might address the low spatiotemporal resolution of current volumetric ultrasound systems. However, to date, it remains unclear how much transmit/receive parallelization would be possible using a 3-D MLT system. Therefore, the aim of this paper was to contrast different MLT setups for 3-D imaging by computer simulation in order to determine an optimal tradeoff between the amount of parallelization of an MLT system and the corresponding signal-to-noise ratio of the resulting images. Hereto, the image quality of several MLT setups was estimated by quantifying their crosstalk energy level. The results showed that for the tested setups, 4MLT broad beams and 9MLT narrow beams with Tukey ( α = 0.5 ) apodization in transmit and receive give the highest frame rate gain while maintaining an acceptable interbeam interference level. Moreover, although 16MLT narrow beams with Tukey/Tukey ( α = 0.5 ) apodization did show more pronounced interbeam interference, its gain in frame rate might outweigh its predicted loss in image quality. As such both 9MLT and 16MLT narrow beams were tested experimentally. For both systems, four receive lines were reconstructed from each transmit beam. The contrast-to-noise ratio of these imaging strategies was quantified and compared with the image quality obtained with line-by-line scanning. Despite some expected loss in image quality, the resulting images of the parallelized systems were very competitive to the benchmark, while speeding up the acquisition process by a factor of 36 and 64, respectively.