Program Keynote Guihai ChenProfessor, Nanjing University Blockchain in IoT: Challenges and Opportunities Dusit NiyatoProfessor, Nanyang Technological University Toward Secure Blockchain-Enabled Internet of Vehicles: Optimizing Consensus Management Using Reputation and Contract Theory Jian WengProfessor, Jinan University Onionchain: Towards Balancing Privacy and Traceability of Blockchain-Based Applications Gang HuangProfessor, Peking University Blockchain-based Ubiquitous Interoperability for Social-Cyber-Physical Convergence