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The article examines the results of the football reform in Russia associated with the change of the season of the Premier League championship. The data analysis shows a decrease in the level of competitive balance in Russian football after the calendar reform. The change in the degree of economic inequality of clubs at the same time, calculated on the basis of the transfer cost of clubs, showed that this inequality could not be the reason for the decrease in the level of competition. On the basis of the correlation and regression analysis, a positive correlation between the indicators of the national championship and the rating of the national team was established. Thus, we can talk about the negative impact of the calendar reform on the success of the Russian national team.

The increasing use of Unmanned Aerial Vehicles (UAVs) in safety-critical missions in both civilian and military areas demands accurate and reliable navigation, where one of the key sources of navigation information is presented by Global Navigation Satellite Systems (GNSS). In challenging conditions, for example, in urban areas, the accuracy of GNSS-based navigation may degrade significantly due to user-satellite geometry and obscuration issues without being noticed by the user. Therefore, considering the essentially dynamic rate of change in this type of environment, integrity monitoring is of critical importance for understanding the level of trust we have in positioning and timing data. In this paper, the dilution of precision (DOP) coefficients under nominal and challenging conditions were investigated for the purpose of integrity monitoring in urban environments. By analyzing positioning information in a simulated urban environment using a software-based GNSS receiver, the integrity monitoring approach based on joint consideration of GNSS observables and environmental parameters has been proposed. It was shown that DOP coefficients, when considered together with a number of visible satellites and cut-off elevations specific to the urban environment carry valuable integrity information that is difficult to get using existing integrity monitoring approaches. This has allowed generating indirect integrity measures based on cut-off elevation and satellite visibility that can be used for UAV path planning and guidance in urban environments.

Unmanned aerial vehicles (UAVs) have shown tremendous potential in both military and civilian applications, for example, in delivery services, search and rescue, and surveillance. Currently, UAVs can perform several tasks while in flight. UAVs have real-time systems with limited capability for time-triggered synchronization, which impose synchronization limitations for their platforms. Additionally, there is no time-triggered synchronization between the UAVs and the ground station. One of the requirements for a reliable communication links between a UAV and a ground station is the need for synchronization using Global Navigation Satellite System (GNSS) in a time-triggered network. However, the information exchange between UAV and ground station lacks the time-triggered abilities. In this context, GNSS time can be used as an external source to allow UAV performing tasks connected to the ground station with time-stamped messages. In this paper, we investigate the capability of GNSS as an external time source for the time-triggered network to achieve high quality of service (QoS) of a communication link between the ground station and UAV. Simulations analysis was conducted to evaluate the overall system performance, which gives a better understanding of performance of a time-triggered wired and wireless network

Satellite navigation systems such as the Global Positioning System (GPS)makes it possible for users to find their relative or absolute position. Thanks to its mobility and reliability, the GPS is used in many civil and military applications. However, the GPS does not provide an advanced level of security. Therefore, it could be potentially a target of attacks. With the development of new GPS attacks, the security knowledge has to grow at the same rate, so existing attacks can be detected by updated versions of receiver software or hardware. In this paper, a comparative analysis of GPS receiver resilience to software attacks is performed with the help of GNSS simulator from Spirent. The main objective of this work is to perform a sensitivity analysis of variables involved in calculation of position of the GPS receivers from different price bands that might be targeted by existing or future GPS attack. Variables making the biggest impact on calculated position are determined using the model. Experimentation validation of their influence is performed using selected receivers and corrupted signals generated by GNSS simulator. The testing is based on tuning the selected variables in order to simulate the theoretical error obtained from the sensitivity analysis. The results obtained from testing are discussed in order to analyse the behaviour of the considered GNSS receivers (including the premium class ones)and establish whether they provide a protection from existing or potential GPS attacks.