Polish Air Force University

The European Geostationary Navigation Overlay Service (EGNOS) augmentation system can be used in air, sea, and road transport. In the case of the latter, an important aspect is its application in the field of car navigation. The main objective of this work is to develop an algorithm and computational strategy for determining the accuracy of a car's position based on a multi-receiver GPS solution with EGNOS corrections in navigation. In particular, the article proposes determining the coordinates of a car based on a mathematical equation of the center of the segment connecting two Global Navigation Satellite System (GNSS) receivers placed on the roof of the car while driving. A total of four GNSS receivers were used for this purpose, two for each geometric segment. Thus, the center coordinates for two independent segments that intersected at a single point were finally determined, where a fifth GNSS receiver was installed to verify the coordinates obtained from the GPS/EGNOS solution. This made it possible to determine the center coordinates of the car while driving. The study used actual GPS/ EGNOS kinematic data recorded by on-board GNSS receivers. The obtained results of the center coordinates of the geometric section were compared with the reference position of the movement for the purpose of calculating accuracy. Based on the tests performed, it was found that the average positioning accuracy is higher than 0.80 m for all BLh geodetic coordinates. The Kalman filter was also used in the study, reducing positioning errors by up to 40% for all BLh components. The developed methodology and calculation strategy can be used, for example, in air navigation for aircraft positioning.

Emergency Medical Services (EMS) trainees are exposed to multiple occupational hazards during their training; however, the extent to which their awareness translates into safe professional behaviours remains unclear. This study aimed to assess the level of occupational hazard awareness and safety-related knowledge among EMS students in the Makkah region, Saudi Arabia. A cross-sectional study was conducted among 96 EMS students from three academic institutions. Data were collected using a structured questionnaire adapted from previously published instruments assessing demographic characteristics, awareness of occupational hazards, safety-related measures, and sources of information. Descriptive statistics and inferential analyses using non-parametric tests (Mann-Whitney U, Kruskal-Wallis), Chi-square/Fisher's exact tests, and Spearman correlation analysis were applied. Overall, students demonstrated moderate to high awareness of occupational hazards, particularly regarding hand hygiene and personal protective equipment (PPE). Lower awareness was observed for ergonomic risks and procedures for reporting occupational injuries. Physical (83.3%) and chemical (81.3%) hazards were most frequently recognized, while ergonomic hazards were least identified (26.0%). A total of 63.5% of participants reported encountering aggressive patients at least once per year. No statistically significant association was observed between academic progression and awareness (p = 0.14). A weak, non-significant correlation was found between awareness and self-reported safety-related measures (r = 0.182, p = 0.076), suggesting a limited association between knowledge and reported safety behaviours. Although EMS students demonstrate generally high awareness of occupational hazards, this may be insufficient to ensure safe behaviour, as reflected by self-reported safety-related measures. These findings highlight the need for educational strategies that better support the application of knowledge in practice.

INTRODUCTION:The COVID-19 pandemic exposed structural weaknesses in European public health systems while simultaneously accelerating institutional and digital reforms at the European Union (EU) level. This study examines how the EU has evolved from reactive crisis management toward a governance paradigm conceptualized as transformative resilience, understood as the institutional capacity to anticipate, adapt, and structurally reconfigure health governance in response to systemic shocks. METHODS:This study employs a structured qualitative policy analysis based on a purposive corpus of key EU legislative and strategic documents (2020-2025), complemented by a contextual review of selected EU-level indicators. The analysis focuses on reforms associated with the European Health Union, including the establishment of the Health Emergency Preparedness and Response Authority (HERA), the development of the European Health Data Space (EHDS), and the adoption of the Artificial Intelligence Act. RESULTS:The findings indicate progressive consolidation of supranational coordination mechanisms, deeper integration of digital infrastructure into health governance, and strategic incorporation of health security into the EU's broader security architecture. Rather than assessing policy effectiveness, the analysis documents a structural and regulatory shift toward anticipatory and embedded preparedness. Persistent challenges remain, including uneven implementation capacity across member states, disparities in digital maturity, and tensions between innovation and data protection. CONCLUSIONS:The EU's post-pandemic trajectory reflects a distinctive governance model in which health security, digital sovereignty, and democratic safeguards are framed as mutually reinforcing dimensions of resilience within an increasingly complex risk environment.

The article presents a methodology for determining the positioning accuracy parameter of GPS with EGNOS and SDCM corrections in air navigation. Namely, the aircraft positioning accuracy parameter was determined as part of a joint GPS/EGNOS+GPS/SDCM solution for two GNSS satellite receivers. The calculation scheme itself was divided into two stages, i.e., first, the accuracy was estimated based on raw GPS/EGNOS+GPS/SDCM data for both GNSS receivers, and then a Kalman filter was applied to improve the determined position of the aircraft, and the accuracy was determined again. The article used the research material collected during an airplane flight around the EPOD airport. The algorithms for the research methodology were written in script in language of Scilab v.6.1.1. During the research, accuracy term was better than 2.94 m. After Kalman filtering, position errors were reduced to 14% for horizontal components and 20% for ellipsoidal height. This allowed for a reduction in position errors below 2.35 m. The paper also calculated other statistical errors, such as: MAE, RMS or standard deviation. In this paper, the characteristics of SBAS corrections were taken into account in terms of determining the accuracy parameter. In particular, the results of SBAS corrections, such as: long-term and fast corrections, ionosphere and troposphere delay. During the research, in addition to accuracy, the availability, continuity, and integrity of GPS/ EGNOS+GPS/SDCM positioning in aviation were also calculated. The presented research method can be used in aviation to increase the accuracy term using the SBAS support systems.

Low-velocity impact and delamination are critical issues for composite structures. One promising approach to improve their resistance is the hybridization of synthetic and natural fibers. However, the impact behavior of such hybrid composites is still not sufficiently understood. In this context, this study presents an experimental investigation of hybrid composites reinforced with carbon, glass, and seven-year-old Bambusa vulgaris fibers from Cameroon in an epoxy resin matrix. The laminates investigated were carbon/Bambusa vulgaris/glass/glass/ Bambusa vulgaris/carbon (CBGGBC) and carbon/glass/glass/carbon (CGGC). The specimens were manufactured via vacuum-bag resin transfer molding using SR 8100/SD 8824 epoxy resin. Five tests were conducted: lowvelocity impact tests, DCB, DMA, flexural, and density analyses. The CGGC hybrid showed a consistently high flexural modulus, ranging from 48 to 55 GPa. Conversely, the CBGGBC hybrid displayed different bending behavior, with higher bending forces from 840 to 1550 N and a flexural modulus between 3.3 and 6.3 GPa. Comparative analysis of thermomechanical and DCB results highlighted the significant effect of Bambusa vulgaris fibers, with a two-tailed t-test at alpha = 0.05 confirming that fibers from 7-year-old Bambusa vulgaris significantly influenced the composites' thermomechanical and mechanical properties.