Dear Colleagues,

    The purpose of this Special Issue on Cyber Security, Smart Cities, and Big Data Optimization in Energy Applications is to deeply inquire, holistically reflect, and comprehensively expose the current and emerging cutting edge technology in important fields of investigation and facilities for original, innovative, and novel real-world applications of Optimization in the modern world related to the emerging areas of the Big Data, Data-based Cryptography and its emerging applications to individuals, groups, cities, countries, etc. During previous decades, the analytical toolbox and the methodological tools of computer science and applied mathematics, of informatics and statistics, of emerging analytics and information technologies has gained the attention of numerous researchers and practitioners worldwide, providing a strong impact also in natural sciences, engineering, economics and finance, the IT sector and, in recent years, the sector of Security, e.g., in data storage, data handling, data transfer, in traffic, transportation, supply chains, etc. Here, Optimization turns out to be a key technology from an integrated perspective, and it is closely connected with further areas of modern Operational Research such as Development, Societal Complexity and Ethics, in order to appropriately address aspects of living conditions, safety and freedom, in culture and environment with regard to that new and fast growing industry. Big-Data based and Security-oriented techniques are more and more wellknown and employed in research areas of engineering, science and technology. Current trends on application problems in engineering, science and technology are also expanded into the areas of economy, finance and, especially, into the hotel, tourism, travel and urban managements across the globe. This special issue focuses on best and high-quality selected papers in a rich variety of research topics. Well-known and new methodologies of optimization techniques will be used to resolve some of the very complicated and hard problems related to our research subjects.

    Contributing authors of this special issue will be experienced scientists and practitioners from all over the world; they use and further refine the deep model-based methods of mathematics and the less model-based, also so-called smart or intelligent algorithms with their roots in the engineering disciplines, in computer science, and informatics. The second ones are often called as heuristics and model-free; they are less rigorous mathematically, released from firm calculus, in order to integrate nature- and, especially, bio-inspired approaches to efficiently cope with hard problems. The rise of these algorithms from Artificial Intelligence happened in parallel to the powerful progress in mathematics that is model-based mainly. Today, labeled by names like Statistical Learning, Machine Learning, Metaheuristics and Matheuristics, and by Operational Research, model-free and model-based streamlines of traditions and approaches meet and interact in many centers of research, at important congresses, in leading projects and agendas in all over worldwide to overcome misunderstandings and misperceptions between these two academic avenues, but to gain from synergy effects, to jointly advance scientific progress and to provide a common service to the solution of urgent real-life challenges. Those vast problems exist in every area of the modern world and academics, in engineering, economics, social, life and human sciences, in development and the improvement of living conditions and future perspectives. Among the variety of these subjects and, in fact, including them all, we guest editors selected the fields of Cyber Security, Smart Cities, and Big Data Optimization. This special issue provides an innovative cutting edge research methodologies and applications in the research field of cyber security, smart cities, and big data optimization which currently popular across the globe.

Prof. Dr. Ugo Fiore
Dr. Pandian Vasant
Prof. Dr. Gerhard-Wilhelm Weber
Dr. Joshua Thomas
Guest Editors

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• Smart City
• Cyber Security
• Mobile Ad Hoc Networks
• Information Network
• Graph Database
• Quality of service
• Internet of Vehicles
• Internet of Things (IoTs)
• Block Chain
• Interoperability
• Machine Learning
• Meta-heuristics
• Supply Chain
• Path Relinking
• High Speed Train
• SMS Security
• Environmental sustainability
• Remote SensingATM Replenishment
• Bit-Vector Encoding
• Electroencephalogram
• Social Network Analysis
• Fuzzy Regulator
• Mobile Cloud Computing
• Web System Diagnosis
• Deep Learning
• Smart and Autonomous Vehicles
• Energy Saving
• Vehicular Network
• Hybrid Renewable Energy