## 3 QualiChain Architecture, Pilot Concept, Research Questions, and Execution Methodology
### Pilot Concept and Stakeholder Needs  
The pilot that was executed in the context of the present publication focused on the optimization of the teaching process, the curriculum, and the university operation as well as the acknowledgment and verification of skills and qualifications of undergraduate and Ph.D. students in a university setting. The pilot was applied in the ECE School of the NTUA, which is one of the oldest academic institutions for technical education in Greece. The ECE School of the NTUA is currently home to more than 2000 undergraduate students, 800 Ph.D. students, and 75 professors. As such, this pilot use case allowed us to test the QualiChain platform in an institution that includes technology-related courses from manifold fields, and hence offers the alumni the possibility to follow multiple potential career paths. Specifically, this pilot revolved around the following actions. * Providing students (undergraduate and Ph.D.) with the tools that can help them build their academic/professional profile. Analytics and decision support functionalities provided recommendations for the improvement of a student's profile. * Provision of analytics and recommendations for the restructuring of the ECE School's curriculum. * Leveraging a trusted, immutable, and secure blockchain ledger to award students and lecturers with smart badges to accredit them for their performance and recognize their work and experience. This pilot leveraged the computational intelligence stemming from QualiChain's analytics and decision support tool [2] to suggest modifications to specific courses and by extension the ECE School's curriculum as a whole, so that the curriculum can be modernized and include the skills that are required to succeed in the current labor market. In addition, both the undergraduate and Ph.D. students at the school were able to receive personalized recommendations that helped them effectively select university courses, open courses, and extracurricular activities. Those recommendations were based on students' completed courses, preferences, QualiChain profile, and desired career paths. More importantly, this pilot utilized the platform's blockchain component to provide student and lecturer accreditation and validation through the endorsement of smart badges that validate specific skills with verifiable micro-accreditations. QualiChain, through this pilot, enabled the verification of not only hard skills (e.g., \"capacity to code in Python\"), but also soft skills (e.g., \"communication skills\", \"teamwork\", \"leadership potential\"), which are admittedly very difficult for employers and recruitment agencies to validate. As of now, such skills are assessed via interviews and tests that assess the emotional intelligence and soft skills of candidates. By providing proof of such qualifications in a verifiable manner (through their addition in the smart badge ecosystem that was created), this pilot brings out the potential to significantly facilitate and expedite the evaluation of prospective employees. The actors that were involved in this use case are undergraduate and Ph.D. students, and professors. * Undergraduate students: One of the students' main needs revolves around the selection of courses that are the most interesting to them and can facilitate the improvement in their skills and knowledge so that they will be better prepared to enter the labor market upon graduation. As of now, there is a lack of technical infrastructure, organized databases, and recommendation systems that could help students at the university choose suitable courses. In addition, there is currently no way to verify specific skills of students, such as advanced knowledge of a specific programming language, which is a significant problem when it comes to proving their qualifications to potential employers. As such, QualiChain provided students with the opportunity to have their own personal profile that enables the quick verification of skills and qualifications gained from completing courses and projects.