Scientific Journal of Silesian University of Technology. Series Transport

11

Authors: Babra DURI

Women, particularly in developing countries, rely heavily on public transport for their daily commute. This study explores the safety and security of women using ride-hailing services in Gauteng. Specifically, the study seeks to understand women’s experiences using ride-hailing services, which might influence their mobility. This study employed a constructivist research philosophy, utilizing qualitative, semi-structured interviews to explore the experiences of women who use ride-hailing services. The study findings reveal several disturbing incidents reported by female passengers using ride-hailing services; however, it is important to note that not all drivers exhibit inappropriate behaviour. Some drivers make inappropriate remarks, while others exhibit rude behaviour. The study found that some drivers use longer routes, leading to higher fares, which can be seen as exploitation. The study also reports some incidents where ride-hailing drivers almost kidnapped some female passengers, indicating a severe safety concern. The study contributes to the ongoing discourse on gender and transport studies, providing empirical evidence on the experiences of women using ride-hailing services in Gauteng, South Africa.

13

Authors: Metin Mutlu AYDIN, Dimitris POTOGLOU, Liana CIPCIGAN

In the current literature, it is clearly seen that most of the traffic chaos is generally observed at intersections of the urban roads in cities. On the other hand, many current traffic studies and research prove that fixed-time signalized intersections cannot have a good ability to control and manage current traffic flow at signalized intersection legs. For this aim, intelligent intersections were developed and started to be used in many cities all over the world in the last decade. These new intelligent intersection systems suggest dynamic signal times for all intersection legs by using real-time measured traffic data. These systems generally use cameras or loop detectors, which are located in the proper places on a signalized intersection leg and record vehicle movements. Within the scope of this study, a performance comparison was made for before and after the camera-based intelligent intersection applications at three isolated pilot signalized intersections within the scope of the "Smart City Traffic Safety" project, which is one of the largest Intelligent Transportation System projects in Turkey. After the system was activated, it was observed that the drivers had impatient behaviors in the beginning and had difficulty getting used to these new systems. After the signal cycle was regulated with the learning of artificial intelligence, it was seen that the drivers had more patience and more observant behaviors. It was also obtained from the analysis results that these new intelligent systems resulted in an average 16% decrease in control delays and a 20% decrease in vehicle speeds.

13

Authors: Ermilso DIAZ, Mariela MUÑOZ-AÑASCO, Antonio CORRECHER-SALVADOR

Fleet systems are considered complex due to the interaction between their units and components. Maintenance management systems face various challenges to achieve acceptable availability and reliability rates at a reasonable cost. A critical task for making maintenance decisions is understanding the system requirements to select maintenance policies appropriate for the actual and future system state. When there is a replacement shortage in a fleet system, and it is impossible to supply new spare parts quickly, cannibalization policies can mitigate this scarcity via the interchange of components. However, this procedure presents the maintenance manager with different evaluation effects, such as increased maintenance hours, decreased system reliability rate, and unavailability in some units. Finding an equilibrium between the benefits and risks has caught the attention of researchers. This work gathers diverse proposals for applying cannibalization policies and the effects that arise from using them. Models, methods, tools, and identified gaps in understanding what parameters of the components and environments of the fleet systems favor cannibalization are discussed.

14

Authors: Elżbieta MACIOSZEK, Irena JURDANA

The article presents the issue of the transport of goods in relation to sea transport. Sea transport has been known to mankind for a long time. Currently, maritime transport is not limited only to the transport of goods and/or passengers along sea routes, which are carried out between seaports using appropriately adapted means of transport. It is a branch of transport, which consists of a very good knowledge of navigation, highly specialized staff, and a wide range of containers for transporting various types of cargo, often requiring specialized conditions. In addition, sea transport is perfectly combined with intermodal transport, so that in the end, the transport process is the most beneficial for all participants, i.e., the customers, sellers, distributors, and manufacturers. The main purpose of the article was to present the volume of goods transported in this branch of transport. The article, after introducing the issue, presents the classification of sea vessels, refers to the market of maritime transport services and its conditions for further development, and analyzes the overall volume of goods transported in the seaports of Gdańsk and Gdynia against the background of other Polish seaports in the years 2011-2021.

17

Authors: Kacper CIEŚLAR, Stanisław PŁONKA

The development of the modern automotive industry requires a quick adaptation of new production methods. This is possible thanks to software capable of simulating manufacturing processes. The paper discusses the modeling of the machining operation of a crankshaft’s crankpins for a diesel engine with the use of the planetary milling method. i.e., modeling of milling operation when a disc milling cutter, having its cutting inserts directed inwards, is performing rotary motion, and at the same time, the axis of this milling cutter circulates around the axis of a machined crankpin. For this purpose, a geometrical model of the machining of the crankshaft’s crankpin has been developed. Based on the design documentation of the crankshaft of the 4C90 type diesel engine and the documentation of the Steyr internal disc milling cutter, their CAD models have been developed, and the both models were linked together with suitable kinematic dependencies. In the next step, the crankpin having a length of 25 mm was divided by planes (in quantity lp=21) into 1.25 mm sections. On the main cutting edge of two cutting inserts of the disc milling cutter, points were marked at intersection locations with these planes. Using the Inventor 2016 system, twelve spline curves have been generated for each plane because each plane intersects 12 cutting inserts mounted in cassettes positioned around the circumference of the body of the disc milling cutter. Next, the spline curves were brought to a common coordinate system, rotating them at an angle resulting from the positioning of the cassettes with cutting inserts in the body of the disc milling cutter. Prepared in such a way, spline curves were written in dwg format, which allowed for trimming of the spline curves at the circle with a radius of rcp = 27.90 mm, corresponding to the radius of the crankpin after milling, considering grinding allowance (ø55h6 + 0.80 mm grinding allowance). As a result, it enabled to leave sections of the arcs tangential to the diameter ø55.80 mm and, in such a way, generate the outline of the shape of the crankpin using the REGION command for 21 cross-sections. The outline of the cylindricity of the crankpin was obtained using the strategy of outlines of the roundness, which were generated earlier; this strategy consisted in the collection of 360 points on the circumference of 21 mutually parallel sections cut by planes perpendicular to the axis of the crankpin. To determine the effects of the circular feed rate of the circulating move of the axis of rotation of the internal disc milling cutter on the accuracy of the machining, simulations of the shape of the crankpin were performed for three values of the feedrate: vf = 1200 mm/min; vf = 2100 mm/min and vf = 3000 mm/min. The spline curves with a determined (depending on the duration of the simulation) number of points: 3500, 2100 and 1409 were obtained for each simulation. The calculated cylindricity deviation for the feedrate vf = 1200 mm/min amounted to CYLrck = 0.2272 mm, for the feedrate vf = 2100 mm/min – CYLrck = 0.2406 mm, while for the feedrate vf = 3000 mm/min – CYLrck = 0.2929 mm.

18

Authors: Krzysztof GRZELEC, Katarzyna HEBEL, Maciej HELBIN, Hubert KOŁODZIEJSKI, Olgierd WYSZOMIRSKI

The concept of influencing changes in transport behavior towards sustainable mobility, which is gaining popularity in the 21st century, is free public transport (FFPT). It is estimated that the number of cities in which attempts were made to introduce FFPT exceeds 100. Most of them are located in Europe, especially in France and Poland. FFPT has mostly been restricted to specific city areas or market segments in the hope of increasing demand for public transport services. Because of this, a number of publications on free fare results refer to specific cases in cities. The main aim of this article is to examine the impact of free fares on the behavior and transport preferences of pupils in Gdynia, Poland. On the basis of the study of preferences and transport behavior of the inhabitants of Gdynia, carried out earlier by the team in 2010, 2012, 2015, and 2018, a preliminary description of the behavior and transport preferences of students was prepared. The research of the pupils was conducted twice: before and after the introduction of free travel entitlements. The results of the research carried out, and the data analysis, confirmed that FFPT had no impact on demand for public transport services or the travel behavior of pupils. According to the authors, the lack of positive effects of FFPT on travel behavior in the segment of students, or even more broadly, for achieving the purposes of sustainable mobility, results from the interaction of the following factors: specificity of students' travel behavior determined by the schedule of school activities, pupils' positive attitude to cars as urban transport means, not covering all means of public transport services of FFPT in Gdynia (the city rail is not covered by FFPT), short period of time since FFPT has been introduced. The results of the presented studies could not be verified due to the COVID-19 pandemic. The authors emphasize that before introducing FFPT, politicians should rely on the analysis of anticipated changes in the behavior of residents and the impact of FFPT on the economy of public transport, sustainable mobility goals and political and social results. This article complements the current knowledge on the results related to the introduction of FFPT for a selected group of residents.

20

Authors: Thong Duc HONG, Phat Tan TRUONG, Minh Quang PHAM, Lam Quang TRAN

With the explosion of urbanization, more and more small residential areas with high population density, tiny houses, and narrow roads are formed. As a result, it is challenging for large fire engines to penetrate these areas in the event of a fire incident. In this paper, a compact firefighting vehicle was designed based on the SNAPPER LT140H331KV lawn mower. The vehicle is equipped with a water sprayer system and a folding frame water tank. The water sprayer system transmits power from the lawn mower transmission’s power take-off shaft via the belt and chain drive, which can spray water at a height of about 13 m with a flow rate of 38 L/min. The 500-liter folding frame water tank has a rectangular shape that can be folded and dragged as a trailer. The water sprayer system and folding frame water tank not only have a simple, compact structure but also do not affect the lawn mowing function. This fire truck has a maximum speed of about 15 km/h and can move in a minimal road width of only 1.3 m, which is accommodation for residential areas within a 1÷2 km radius with narrow roads, high density of population and houses in least developed and developing countries (e.g., Vietnam, Laos, Cambodia), where the normal fire engines are difficult to access in time. Besides, the vehicle can be used for watering and spraying pesticides on gardens and small premises. The study has proposed a valuable solution to take advantage of vehicle functions to improve their convenience and usefulness.

22

Authors: Marzena PIOTROWSKA-TRYBULL, Jarosław KOZUBA, Stanisław SIRKO

Airports, as a component of air transport, combine air transport with other modes of transport to strengthen the transportation accessibility of a place in space, attract investors, and stimulate the development of the area. Taking into account that these issues are less exposed in relation to their immediate surroundings, research was undertaken to determine how representatives of the authorities and residents of communes (taking into account the nature of the communes and the size and location of the airport) perceive airports, located within their communes, in the context of their impact on the socio-economic situation in the communes. This was achieved by analysing the communes' strategic documents and data on the operation of communes and airports from 2016 to 2021. These data were obtained from the Civil Aviation Authority, the Central Statistical Office, the International Air Transport Association, and the International Airports Council. In an effort to better understand the relationship between the airport and the commune in which it is located, poll research was carried out using survey and interview techniques. The research focused on 10 airports spread across Poland. A total of 1,200 surveys were conducted among residents of communes, and 10 interviews were conducted with representatives of local governments and the port. To analyse the collected data and present the results, Statistica v.13.3 and R/RStudio software were used.