International Scientific Journals
of Scientific Technical Union of Mechanical Engineering "Industry 4.0"

The idea of creating and using digital twins has been strongly influenced by the process of integrating artificial intelligence methods with big data analytics of data from Internet of Things (IoT) devices. The concept of “Digital Twin” has become increasingly influential and culminating in the field of CPS. The main objective of the study is to define the basic requirements to the digital twins for cyber-physical system and based on the different definitions and components of digital twins, to summarize and analyze approaches, methods and tools used for their development. This analysis should serve as a basis for the development of a methodology for creating digital twins for cyber-physical manufacturing systems in the process industry.

Agriculture is a sector in Bulgaria that contributes significantly the GDP. In the past 20 years steady trends for increasing the arable land, while the number of agricultural holdings decreases. The enlargement of the size of the agricultural holdings is strongly associated with the need for implementation of the advances of information and communication technologies, Industry 4.0 and artificial intelligence. The present paper presents the development of an integrated Customer Relationship Management (CRM) system for agricultural applications. The developed CRM system implements the following functions: customer data management, management of contracts for clients, management of agricultural land, management of processing costs, production revenue management. For the development of the presented integrated CRM system, the needs of the agricultural producers and the work with their clients have been studied in detail.

The IEC-62541 (OPC UA) standard is an important part of the Industry 4.0 reference architecture and is recommended as the only possible communication standard. A particularly important issue that is being addressed is the issue of security. Cyber security is one of the most important challenges for achieving the objectives of the Industry 4.0 initiative and of the associated cyber-physical systems (CPS). The paper analyzes the vulnerability of cyber-attacks and the main threats that threaten the security of OPC UA-based CPS and defines proven and sustainable recommendations for increasing the security of these applications.