Stelios Vretteas Email & Phone Number

Member of the Data Platforms section, my main contributions among others include:● Maintenance and support of existing Datawarehouse for Energy Management:Maintain existing SSIS packages, SQL Server database, Azure Analysis Services tabular models, and PowerBI reports.● Revenue Assurance for Finance Department:Design and implement daily, weekly, and monthly controls over the billing and CRM systems to identify errors in order to minimize revenue leakage. ● BI Solutions for Power Plants and other Divisions:Develop regulatory reports on emissions and operational monitoring. Provide actionable insights to optimize power plant performance and ensure regulatory compliance.Automation of Profit and Loss Financial Statement in PowerBI.● Data Platform Design and Development:Participate in discussions and design efforts to build the company’s Data Platform using MS Fabric technology, contributing to future data infrastructure strategy and reporting.

Member of project team for the design and implementation of BI, DWH, DM and DG solutions for the following clients:● Major Energy Company: Involved in the Data Governance Realization and Master Data Management project. Collected existing business related reports and metadata, identified source systems and defined Master Data Records. Created training material regarding Data Governance roles (Data Steward, Custodian, Owner) for Company's employees.● Major Hotels Group: Involved in the Enterprise Data Warehouse (EDW) project on Azure Cloud. Designed, built, tested and deployed ETL flows and processes to move and transform enterprise data from Group's on premises systems and 3rd Party API providers, utilizing Microsoft Azure platform (Data Factory, Azure SQL, DevOps, Function Apps). Re-designed the existing reports and created new ones using Microsoft's PowerBI.● Major Retail Company: Involved in the Digital Transformation project. Designed and implement the solution for Finance and Sales reporting utilizing Microsoft SSIS, SQL Server and PowerBI.● Major Energy Company: Involved in the Project Management System project in order to monitor the performance and progress of the Company's ongoing projects. Created system's schema in Synapse Analytics, implemented ETL mechanisms with Azure Data Factory, created business reports with PowerBI.● Major Real Estate Company: Involved in Content Management System project in order to establish the Company's sales procedure. Analyzed and improvised the Company's Sales function, supported the develoment team, designed the suggested solution Blueprint.

Member of the Archimedes Unit as postgraduate student, designed and built a prototype tool-application that solves the problem of predicting the occupancy of a public mode of transport (trolleybus or bus) using LSTM models.

Greece

Master'S Degree, Business Analytics, 8.64

Thesis: Data Privacy & Fairness in Machine Learning. The concept of my Thesis was the algorithmic fairness through classification.

Bachelor'S Degree, Economics