A Study of the AR Solutions Used in the Dangerous Goods Acceptance Process in Airport Cargo Warehouses  
[PERSON]  
1 Faculty of Mechanical Engineering, Department of Technical Systems Operation and Maintenance, Wroclaw University of Science and Technology, Wygianskiego Street 27, 50-370 Wroclaw, Poland; agnieszka.tubis@pwr.  
between a human and a digital system [2; 3]. In contrast to the virtual continuum provided by VR, AR lets one overlap relevant virtual elements onto observed reality [4]. This makes the technology a great tool for enriching one's senses with additional data which would not be accessible without an AR tool. Reality can be \"augmented\" by a common mobile device (e.g., a tablet or a smartphone) as well as in a more immersive way--by wearing Head-Mounted Display (HMD) [5].  
The air transportation sector is one of cornerstones for intercontinental and international passenger and cargo traffic [6], and airports serve as crucial hubs for the efficient movement of goods across the world [7]. [PERSON] et al. [7] reports that, in terms of cost, 35% of global trade and 90% of e-commerce is transported by air. Every improvement in this segment of the industry can yield high profits for stakeholders because of the scale of the air transportation market. On the other hand, the great number of air cargo operations and the huge potential consequences resulting from a fault occurring when cargo is incorrectly handled or transported makes this sector an area with great potential in regard to improving the efficacy and safety of cargo handling and transporting. The safety of cargo-handling operations becomes of utmost importance, especially in cases where the transported cargo is a \"dangerous good\". The Air Transportation Association (IATA) defines dangerous goods (DG) as \"items that may endanger the safety of an aircraft or persons on board the aircraft. Dangerous goods are also known as restricted articles, hazardous materials and dangerous cargo\" [8]. To assure the safe transport of DG, the United Nations Economic and Social Council (ECOSOC) issued the UN Recommendations on the Transport of Dangerous Goods [9]. They form the foundation for national and international regulatory schemes [10]. With consideration of the recommendations, the International Civil Aviation Organization (ICAO) and the local Civil Aviation Authority Regulations govern their carriage on-board aircraft [8].  
The transport of DGs by flight requires the goods to be prepared according to law regulations. The preparation process is called the dangerous goods acceptance (DGA) process. Its accuracy directly determines the safety of a flight, aircraft crew and passengers. The safety management and risk assessment of DG transport have been considered in the literature, but only a few studies have examined the air transport of DGs. Of the studies that can be found, most of them analyze and investigate air accidents and unsafe incidents with DGs (e.g., [11]), and very few literature findings are concerned with the safety management of DG air transportation from a prevention perspective [10; 12]. The aim of this research is to fill the gap and answer a few cognitive questions on the potential of DGA improvements with the use of AR technology. The answers constitute a contribution to the knowledge regarding AR application in the DGA process carried out in air cargo terminals.  
1. Which operations of the dangerous goods acceptation (DGA) process in an airport reveal the highest potential to be supported by AR solutions?
2. Which parameters of the DGA can be improved by AR solutions usage?
3. What benefits and drawbacks of solutions using AR technology have been noticed in practical experiments?