Blockchain smart contracts can support the decentralisation of business processes, but due to smart contracts’ specifics, their development is a complicated process. Introducing model-driven development principles in smart contract development can facilitate requirement specification, design, and implementation activities. This paper presents a model-driven development method MDAsmartCD (Model-Driven Architecture-based Smart Contract Development) to alleviate smart contract development by supporting the complete MDA life cycle, covering the definition of Computation-Independent Model, Platform-Independent Model, and two instances of Platform-Specific Models. In MDAsmartCD, model transformations (model-to-model and model-to-text) are used to produce smart contract code in the Hyperledger Fabric platform Go and the Ethereum platform Solidity programming languages. The method application was demonstrated by implementing the smart contract for the hackathon solution and executing the generated Solidity and Go smart contracts in the workflow of issuing certificates for hackathon participants. During the execution of the workflow, both deployed smart contracts behaved identically and recorded analogous results in respective blockchain data storages. This demonstrated that the MDAsmartCD method enables the generation of compilable and executable smart contract code, ready for deployment on a blockchain platform.

Computer-guided dynamic navigation systems have elevated dental implant surgery into a more patient-friendly and efficient procedure. However, commercially available systems use displays as an output for guidance. This implies that surgeons have to take their eyes off the surgery site frequently in order to accurately adjust surgical instruments. The solution for such an issue is to use augmented reality (AR) head-mounted devices to showcase all necessary guiding instructions without any distractions. In this work, the implementation of augmented reality in dental surgery using the HoloLens 2 AR headset for the assessment of accuracy is described. The experiments were performed in vitro with two implementation steps, evaluating calibration and perspective of the virtual dental model alignment accuracies using a newly created marker. The calibration results showed overall accuracy and precision surpassing the 1 mm threshold in distance-related measurements. Dependency on the side on which the marker was observed and the movement of the user’s head were considered to be the most influential factors regarding the perspective of the virtual dental model alignment accuracy estimate.