Scientific Journal of Silesian University of Technology. Series Transport

9

Authors: Blerina BEQAJ

Water is one of nature’s resources. As urbanisation grows, new roadways and highways are constructed for the transport sector and development. Due to roadway infrastructure, the development of the quality of surface water bodies in close proximity to roads is deteriorating and has become a major environmental challenge. Considered as one of the major nonpoint pollution sources, the construction of new roadways can have short and long-term effects on water quality conditions. This study revealed that road construction activities may be responsible for introducing pollutants in nearby water sources, leading to the deterioration of water quality. The roadway expansion activities affect both the surface and groundwater quality. Furthermore, this study was conducted to assess the effects of a road construction project situated in the southern part of Albania, on physic-chemical parameters of surface water by collecting water samples from Skotini stream. The analysed parameters included pH, dissolved oxygen (DO), biological oxygen demand (BOD5), chemical oxygen demand (COD), electrical conductivity (ECw), total dissolved solids (TDS), salinity, nitrites (NO2-), ammonium (NH4+) and total phosphorus (Ptot). The results revealed that all physic-chemical parameters analysed in the laboratory are between the normal standards classifying these waters as very clean. Further surveillance for quality assessment of water sources near roadway’s construction activities is needed. Various best management practices have been developed and implemented to prevent negative environmental impacts in the transport sector and roadway construction activities. Results of the water quality help strengthen the theory that roadway construction projects in the transport sector, using appropriate best management practices, could yield minimal impact on the overall water quality of surrounding water bodies.

11

Authors: Agata KUREK, Elżbieta MACIOSZEK

Currently, more inhabitants use a car for their travels. The consequence of the increase in traffic on the roads is the deterioration of road conditions, decrease in the level of road safety, increasing air pollution, as well as the problem of finding a place to park a vehicle. This article analyzes the daily variability of the use of parking spaces in the Paid Parking Zone (PPZ) covered by Dynamic Parking Information (DPI) in Gliwice before and during the COVID-19 pandemic. In the first stage of the work, the daily variability of the use of parking spaces and the rotation indicator were analyzed in parking spaces at PPZ covered by DPI before and during the COVID-19 pandemic. The Wilcoxon test was performed to verify whether the differences are statistically significant. The results indicate that the COVID-19 pandemic contributed to the decrease in the use of parking space and the rotation indicator in the parking spaces at PPZ. In addition, the research shows that collecting fees for parking a vehicle in a parking space increases the use of space and the rotation indicator. Due to this, parking spaces are available for more drivers.

11

Authors: Oleksiy MELNYK, Yuriy BYCHKOVSKY, Andrii VOLOSHYN

The maritime industry is a high-risk industry, which constantly has to make decisions in a rapidly changing environment. Therefore, understanding the essence of "situational awareness" is very important for making the right decision. In this regard, it is obvious that a correct situation analysis, based on a theoretical basis, creates the proper prerequisites for making the right decision in a developing situation, and vice versa. Considering this fact, this article proposes to study the factors that influence this phenomenon, their regularities and connections. It presents the data of a survey among seafarers to determine the level of understanding of situational awareness as a predominant component of the human factor in most accidents in the maritime industry.

12

Authors: Radka JÍROVÁ, Lubomír PEŠÍK

Air conditioning systems in vehicles require long-term reliability during their entire service life. Especially, a good sealing function is needed for the prevention of coolant leaking. Unfortunately, in specific cases, after a particular time, screw connections of the air conditioning circuit lose their tightness, and the coolant starts to leak. Therefore, this paper focuses on the analysis and design optimisation of screw connections. We used the finite element method for describing the sealing, screw and disc spring behaviour. Then, we proposed a new design of the disc spring to obtain the proper force-deformation characteristics of the connection and ensure the tightness of the screw connection.

12

Authors: Vladimir NEKHOROSHKOV, Sergey VAKULENKO, Peter KURENKOV, Evgeniy NEKHOROSHKOV, Grigoriy DERUZHINSKIY, Alexander IGNATENKO, Alyona AROSHIDZE, Alexey ASTAFIEV, Irina SERYAPOVA, Irina SOLSKAYA

The development of international cargo transportation has been relevant since the emergence of the international division of labor. Billions of tons of goods of various names, values and volumes are transported across the borders of the Russian Federation every year. This paper examines the Eurasian Economic Union international transportation system, its transport system integration, and the formation of a common transport space. The authors analyzed the international transport market state and conditions and the level of containerization. The transport system is considered the country's economy "circulatory system", which makes it a key link in the implementation of economic reforms in the country. The transport industry has social significance, which also determines the specifics of the phased market transformations. The development of international multimodal container transportation is becoming a new trend in the development of the transport service market.

12

Authors: Kanala Teja Vinay Kumar REDDY, Surya Prakash CHALLAGULLA

Unexpected delay on freeways is the prime cause of dissatisfaction in road users. Increasing traffic, adverse environmental conditions, accidents, time, season, location and many more factors influence travel time and cause delay. There is no direct method to estimate delay. It is calculated from trip time estimates. Thus, it is a very big challenge for transportation professionals to develop a model that accurately estimates the trip time for a trip at a particular time, by a specific mode of transport. Subsequently, the reliability of the delay calculated from those trip time estimates is often doubtful. Further, the measurement of delay using the trip time data is another big thing. This paper is a step toward measuring the delay in an accurate way using travel time reliability measures. The study was conducted on the two modes of public transportation (City bus and Auto) in an urban corridor of length 16.3 km, in Hyderabad city, India. In this study, a license plate survey was conducted for data collection, travel time-based statistical analysis was employed for estimation of trip time and by making use of travel time measures, the delay was measured. The approach was validated graphically to portray its accuracy.

14

Authors: Greg WHEATLEY, Arash BABAMIRI, Bronson PHILIPPA

Airlie beach houses are quite common in the coastal areas of Australia. These houses, similar to other buildings, provide comfort for their residents. House comfort is not limited to temperature or sound pollution, vibration can be considered as another equally important factor. In this article, the vibration of an Airlie beach house was investigated. The base steel structure was modeled in SolidWorks and Space Gass for evaluating stress distribution and nodal displacement, respectively. To find the root cause of the distressing vibration of the house, which was felt with dwellings, the axial acceleration of the house’s structure was determined. Some feasible solutions such as adding a fiber-reinforced polymer joist hanger, inserting additional rubber padding to the joist hanger, and attaching additional bracing, were discussed and a cost analysis was considered for the solutions. Eventually, the nature of the best solution, which was adding rubber, was tested experimentally.

16

Authors: Mulugeta GIRMA, Berhanu WOLDETENSAE

Rapid urbanization has resulted in a slew of issues, including urban transportation, in most emerging countries' cities. Public transportation provides transportation for the community and plays an important role in the daily lives of the city's citizens, particularly the urban poor, by reducing travel costs and providing job opportunities. Thus, evaluating public bus service performance from the perspective of users is critical for identifying service operators' strengths and deficiencies. Consequently, the primary goal of this research is to determine the level of consumer satisfaction with public bus service in the city and identify the most important factors that influence satisfaction. Hence, a survey was carried out between December and January 2020. Stratified sampling approaches were used to obtain data from 500 travelers. Factor analysis and customer satisfaction index were used to analyze the data collected. Lastly, the findings show that users were quietly satisfied (0.54) with the quality of the bus services supplied in the city. Moreover, travelers were better satisfied with attributes that related to availability (0.64) and less satisfied with attributes under timeliness (0.50) and security (0.48). Therefore, service operators and other concerned stakeholders should give urgent attention to attributes under timeliness and security to enhance users’ satisfaction in the provision of bus service in the city.

17

Authors: Michał ZIĘTALA

This paper presents the stability of the GPS and GLONASS system clocks’ stability. It describes the construction of these two systems and calculated four different Allan variances (AVAR), based on the MGEX (the Multi-GNSS Experiment) clock products. Four used variances allowed making a better analysis of each GNSS system clock. The results are shown at different averaging times from 5 s as successive multiples to 655,360 s in a monthly period. The stability of GPS and GLONASS clocks is included in the range of 10-12~10-14 s. The results showed that GLONASS clocks are stable (10-12~10-14 s) and are affected with white frequency noise (WFM). The GPS clock stability models have more fluctuations for τ > 40,960 s and the mean stability is concluded between 10-12~10-13 s. Mean frequency accuracy for GPS clocks is related with WFM and Random Walk Frequency (RWF). The differences in clock stability are caused by several factors – block type, type of clock and the time of a satellite in orbit. These factors have an influence on stability results.