Functional tests of the ETCS and rail traffic control systems

The paper presents the issues of railway traffic control devices testing and focuses on European Train Control System (ETCS) devices widely implemented in railways. The functions of the ETCS system, principles of operation are described. The basic telegrams transmitted in the track-to-train relation are listed. The process of designing and verifying the implemented data and what parameters are checked at the stage of field tests using the locomotive is briefly described. The functional model of the SRK devices, including ETCS elements, was presented, and the close relationship between the base layer of the railway traffic control devices and the ETCS was shown. Equipment testing reduces the availability of the rail network, engages staff, and generates costs. A test generation method is presented to minimize the impact. Two indicators are proposed for reducing the set of checks, the cost of checking and the information effectiveness. The cost of checking due to the problematic estimate is generalized, divided into three groups taking into account the difficulty and resource consumption of bringing the devices to the initial state and their operation according to the test. Therefore, the obtained set of checks is suboptimal and ensures complete coverage of the functions with tests, which is essential when testing devices. The tests are carried out using available setting commands and the implementation of tasks - entry and exit routes at the station. The proposed method is universal and can be applied to any railway traffic control device, regardless of the manufacturing technology. It is a non-invasive method in the structure of the tested devices and does not require additional hardware resources.

The analysis of aircraft equipment essential for the use of ADS-B, implementation in 2021

The fluidity of air traffic depends mainly on the coherence of the minimum separation requirements between aircraft in the airspace and the advanced exchange of air traffic information obtained through the interoperability of ATM systems and surveillance data exchange systems between aircraft and ATM system. In the paper on the implementation of unified global solutions, ICAO indicated that the key requirement is that the functions of on-ground ATM systems concerning the source of information surveillance (aircraft position). ICAO encourages the widespread use of ADS-B technology (Automatic Dependent Surveillance – Broadcast). The paper presents the concept of using ADS-B, analyzes the problems resulting from the need to ensure interoperability, and shows the results of measurements and analyzes of the actual equipment level of aircraft operating from two airports in TMA Warsaw: Warsaw Chopin Airport (EPWA) and Warsaw Modlin (EPMO). In summary, the authors refer to the level of meeting the requirements of the ADS-B equipment in the context of formal and legal requirements and the time remaining until the published requirements are fully applicable.

Braking of the tractor-semi-trailer set in a rectilinear motion

Because of the increasing share of cargo movement using road transport, the issue of safety hazards related to the movement of trucks and road sets remains an essential element of the overall road safety system. Braking is the primary defensive maneuver in accident situations. The main purpose of this work is to present a simulation method for assessing potential hazards occurring during the braking of an articulated vehicle (tractor-semitrailer combination). A relatively simple, quasistatic mathematical model of road vehicle set braking was presented. Several qualitative and quantitative criteria for safety evaluation were proposed, and a series of exemplary calculations illustrated with time characteristics of the quantities describing the road vehicle set movement. These calculations show that the proposed method may be helpful for the assessment of braking safety depending on the selected factors relating to the operational condition (the way the trailer is loaded, failure of the brake system, road surface condition).

Civil Aviation Flight Safety: Pilot Properties Soft Computing

The commercial competition leads to aviation accidents. It forces airlines to reduce the cost of purchasing, leasing, and maintenance of aircraft. The air carrier saves on professional training of personnel, on an arbitrary increase in the workload standards, on the use of flight crews with minimal and untenable experience in chronic fatigue conditions. Theory and methods of the characteristics of specialists remain uncertain. Statistical data and expertise may be piecewise-defined, inaccurate, and inconsistent. To calculate the dependability of flight crews based on workload and experience, it is necessary to establish indicators and values of acceptable accuracy using fuzzy measures. It is proposed soft computing, statistical and expert methods for calculating the properties of a person and social groups in the management of dangerous professions. This makes it possible to calculate the dependability of the pilot properties with an assessment of flight safety risk levels for making management decisions. The results of the work are new standards for the workload of flight crews recommended for civil aviation. Results are obtained in qualitative methods for calculating efficiency, security, and risk states in the management of organizational objects as airlines. We obtained indicators for air transport risk management standards and decision-making tools. Calculated indicators of pilot dependability values are a model for developing the airline's strategy, for quantitative assessments of flight specialists, standardizing professional activities, and managing training costs.

Classification of innovative wheelchair constructions with the option of transport via stairs

Modern transport systems are developed following universal design, considering the requirements of people with disabilities. Despite the detailed legal regulations in construction and industry, there are still many barriers, e.g., architectural barriers, making it challenging to move around in wheelchairs. Designs of wheelchairs with special capabilities provide a chance to overcome these barriers. The article aimed to present various methods of climbing stairs by wheelchairs with special abilities. The review of works was related to the research work of the scientific team from the Faculty of Transport of the Warsaw University of Technology. Against the background of other works, the author's own design solution was presented.

Assessment of the usability of the EUSAMA and the phase angle method in examining the condition of shock absorbers installed in a vehicle

The article is a continuation of the author's earlier considerations concerning the methods of testing shock absorbers installed in the vehicle. The work concerns the analysis of the usability of two methods: the EUSAMA method and the phase angle method. The first one examines the minimum ratio of the force in contact between the wheel and the vibration-inducing plate (on which the wheel of the tested suspension rests) and the static value of this force. The second one uses the minimum of the phase shift angle between the excitation (vertical movement of the said plate) and the force in contact between the tire and this plate for diagnosis. Two linear quarter-car models and their description in the frequency domain were used to evaluate two analyzed methods. For both evaluated methods, the monotonicity of the dependence of the diagnostic parameter on the diagnosed one (damping in suspension) is visible; in the case of the phase angle method it is close to linear. The correction of the results related to the inertia of the vibration-inducing plate was considered. The calculations were made for two typical data sets: for the front and rear suspension of a middle-class passenger car. They allow a general qualitative and (to a limited extent) quantitative assessment of the usefulness of the analyzed methods. For the EUSAMA method, the test result has a noticeable effect of the inertia of the vibration-inducing plate. This confirms the legitimacy of correcting the force measured in the diagnostic stand. Values without correction are more optimistic. For cars with a low weight or a lightly loaded road axle (especially the rear axle) of heavier vehicles, low values of the diagnostic parameter are obtained, suggesting a bad condition of the shock absorbers, which is not confirmed by their examination in the state removed from the vehicle. In the second assessed method, there are clear differences between the values of the phase angle obtained based on testing the force in the wheel-plate contact and those obtained for the analysis of the force measured in the test stand. Therefore, the correction for the value of the station plate inertia force is significant. Values without correction are more pessimistic, although it is not justified in the condition of the tested vehicle. The works cited in the article describe several practical drawbacks of the phase angle assessment method. The author points to the importance of further research, much more laborious, with the use of nonlinear models and the necessary experimental verification of the obtained simulation results.

The concept of the model of air search and rescue system

The article introduces a short outline of the concept of a scientific approach to the subject of search and rescue. Next, the model presents the mapping of selected assets with an indication of the assets essential for the rescue operation's configuration critical to the system. The crucial elements of the rescue operation that must be included in the model are: determining the location of the sought entity, environmental conditions during the rescue operation, survival conditions at the crash site, available assets (e.g. helicopters, described in the system model), the structure of the necessary commands to manage a rescue operation.

Air traffic safety management: ANSP perspective

The dynamic growth of air operations in the airspace is related to air traffic threats, which obliges aviation organizations to predict them and develop a proactive safety management strategy. The study aimed to analyze how the air navigation service provider (ANSP) implements the safety management system's assumptions in the event of a constant increase in air traffic and whether these activities contribute to achieving the assumed parameters (indicators) of safety. For this purpose, a critical analysis of the literature was carried out, supplemented with interviews conducted among these institutions' representatives. The best tools for implementing the safety management system's objectives, including hazard identification and risk management by ANSP, were identified. These are the safety assessment methodology for changes in functional systems SAM (Safety Assessment Methodology), the mandatory and voluntary reporting of aviation occurrences, and the RAMS risk assessment mark sheets. It should be noted, however, that the change management process concerns primarily planned changes. Simultaneously, there is insufficient information on how to deal with unplanned changes, and the safety culture requires intensified activities in the form of training of operational personnel. Besides, safety regulations require constant updating, and safety management models adapt to a continually changing environment.

Application of modern form of training in the proces of educating candidates on air traffic controllers

The research problem raised in the article is gathering experience and determining the possibilities of implementing modern forms of training used when training candidates for air traffic controllers. For the exercise of determining the separation time between aircraft with different maximum take-off masses, an application was created as part of the research program. As the applied research method, trainees' testing of the developed application at the training center can be considered. They had the opportunity to test the functionality and usefulness of software and ergonomics of created application. During application testing, students shared numerous comments on the usability and application's functions. It was confirmed that virtual reality helps recognize the silhouettes of aircraft and their learning thanks to the possibility of their actual presentation. The possibility of training the use of separation in air traffic before the simulator training starts would lead to preparation and visualization of theoretical knowledge in practical application. Creating an application to determine the separation time between aircraft with different maximum take-off masses has excellent potential for use in the training center. The development of the application consisting in extending this possibility would allow creating a tool that, in addition to training, would also be used as software for conducting internal examinations of the acquired knowledge during the subsequent stages of training.

The concept of logistics facilities database in the EPLOS system

The paper presents results of research on the needs of TSL companies in the field of information on logistics facilities, analysis of existing databases containing such information as well as the concept of a structure of databases on logistics facilities in the EPLOS system. There were also made assumptions regarding the scope of information obtained from existing databases and requirements for them. The EPLOS system - European Portal of Logistics Services is a tool supporting the planning of logistics processes. It also supports the implementation of these processes by providing entities operating in the TSL market with current and verified data on operations in a given area of logistics companies, as well as the availability of point and linear logistics infrastructure. EPLOS system is created as part of a project financed on the initiative of EURE-KA.