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Significant economic growth visible in recent decades in Thailand contributed to a huge demand for private vehicles, which was not followed by a sufficient growth of transport infrastructure, consequently leading to permanent congestion, increase in the number of accidents, high carbon emission and thus a decline in the air quality. This research was conducted in the capital of Thailand, Bangkok using key informant interviews to examine socio-economic determinants of 3 different modes choice: car, motorcycle and public transport. The major findings included the lack of use of public transportation due inadequate transportation schemes and policies at the local and national level in Thailand. Further analytical findings include the social, cultural and economic factors affecting the choices of the mode of transportation in Thailand.

At present, the issue of public safety in the production and manipulation of hazardous chemicals deserves more attention, since various major accidents such as fires, explosions and toxic gas releases take place frequently. The issue of prevention of emergency events has become more and more topical. The growing amount of hazardous substances transported leads to increased risk of emergencies. In order to reduce this risk in the transport of hazardous substances, a number of technical, operational, traffic and safety conditions and requirements must be fulfilled. These all contribute to the reduction of hazards and risks. The aim of the presented article was to determine the extent of the danger zone in the event of a gasoline leak due to a traffic accident in a built-up urban area with a high frequency of traffic and population movement.

The paper presents an analysis and comparison of selected dynamic parameters in the common crossing and switch unit of a railway turnout. The paper includes a description of the measurement methodology, the report of mathematical methods used to evaluate the measured data and comparison of selected parameters describing dynamic processes in individual parts of the structure. The paper also includes a mathematical analysis of the lesser-known Hilbert Huang transformation, including its practical application. From the presented case study, practical experience and recommendations for the railway line managers, research organizations and possibly for the wider technical public are derived.

The purpose of the proposed study was to identify the functional patterns of influence of the marketing tools on sales of cars on the global market, to be able to predict sales volumes in the future, taking into account certain marketing tools that the company may use in a particular international market. For the purpose of this research the method of correlationregression analysis is used to construct the corresponding economic and mathematical models of impact on the sales volumes of various instruments of product, price, promotion policy, etc. Using the models offered in the article, the feasibility of introducing certain measures can be determined, when entering new markets in order to increase car sales. Each instrument to which potential buyers are sensitive determines the effect of its use. Considering this effect, budgets can be set up for appropriate action.

Traffic congestion is a major problem around the globe. The prime reason for congestion is unavailability of traffic infrastructure to meet the traffic demand. Road users are forced to face undesirable delay, which influences the economy, environment and health. The present study examines the congestion in the urban roads of Bhubaneswar, a smart city in India. Travel time for various categories of vehicles was estimated and congestion indices in terms of buffer index were evaluated. Multiple linear regression modeling has been used to evaluate the congestion parameters. The p-value for all the independent variables in the developed model is < 0.05. Four elements, namely Strict traffic law implementation, Adequate parking facilities, Decentralization and Controlling the road side activities are required to improve the serviceability and mobility of urban road networks.

This paper deals with implementation of artificial neural network in the maximum power point tracking (MPPT) controller algorithm for modern household where electric vehicle (EV) was purchased. The proposed MPPT algorithm was designed to achieve the best possible efficiency of the MPP (maximum power point) tracking and the best possible energy harvesting to charge the EV's battery. The artificial neural networks have strong advantage in fast input to output response of signals and the finding of MPP is faster than in commonly used algorithms. In this article, the optimised simulation model based on artificial neural network will be introduced. The proposed artificial neural network algorithm was designed for non-shielded photovoltaic panels.

The long-distance travel (LDT) mode choice modeling is important for transportation planners. This study investigated alternative mode choice behavior for the LDT between the intercity buses and trains. A questionnaire survey, consisting of important mode choice attributes, was conducted on various groups of people in Bangladesh. Numerous travel mode choice contributing features (e.g., travel time, travel costs, origin-destination, comfort, safety, travel time reliability, ticket availability and schedule flexibility) were considered and the LDT mode choice models were developed using various machine learning algorithms typically applied for classification problems. With 95.31 % accuracy and 0.95 F1-score, Random Forest model was the best performing model for the dataset. According to the findings of this study, the intercity bus is preferred over the intercity train for LDT in Bangladesh.

The study carried out an analysis of the vehicle traffic parameters on a national road in 2011-2016. The variability and uncertainty of results were evaluated. An analysis of traffic data recorded on the city's entry and exit lanes was carried out. The variations in traffic volume are of interest e.g. in dynamic traffic management systems and navigation services, examining the benefits of flexible work time and places and assessing the environmental effects of traffic congestion. Research has shown that the assumption that lanes perform equally is not always true. Traffic volume models should be periodically calibrated taking into account the shape of the daily profile, which may, for example, allow public transport timetables to be more responsive to the needs of travelers.

The first and last mile part of the public transport journey are essential for the whole transport system. Its quality affects the overall experience of the passenger in public transport. It is not important how attractive are individual transport modes if the rest of the journey is unattractive for the passenger. This paper is about shared mobility and it describes the connection between the first/last mile and the public transport system. Modes of shared mobility can reduce the pressure on the city transport system. It can also bring a better modal split. The authors performed a traffic-sociological survey for processing the respondents' opinions on the use of new modes of the sharing economy. The survey showed that more than eighty per cent of people travel to work daily, but more than half of them do not use public transport.

Present study evaluates the various congestion indexes in terms of speed performance index, volume to capacity ratio and congestion index based on travel time on the urban roadway network of 5.7 km in length, operating with mixed traffic conditions (traffic with varying static and dynamic characteristics of vehicles). The mitigations measures have been proposed to cater to the present traffic demand by converting the uncontrolled intersection to a partially controlled or signal-controlled intersection. In order to check the effectiveness of such mitigation measures, various scenarios have been generated in the developed and a well calibrated simulation model. It has also been observed that the speed performance index has improved by 8.88 percent while providing channelized intersection at one of the point elements and 11.52 %when the two-point elements have converted to channelizing intersection.

The article deals with the problem of estimating the rational number and utilization rate of the vehicles' fleet. According to the analysis results of the state-of-the-art literature it has been revealed that the issue of substantiating the rational fleet size and the rate of its utilization were not fully solved. The purpose of the study was to increase the efficiency of servicing transportation orders by determining the required number of vehicles. The goal of the research was the influence of the transportation process parameters on the truck utilization rate. Originating from the probabilistic nature of the transportation process, it has been proposed to use the AnyLogic software product to develop a simulation model for vehicle orders' servicing. From the processing of the experimental results by the regression analysis methods, it has been found that the dependence of changes in the vehicle utilization rate is of a linear form.

Angular ball bearings are commonly used whenever there is a demand to increase stiffness of a bearing. The aforementioned increase of stiffness can be achieved by obtaining proper preload in bearings. In common belief, preload has a negative consequence: it increases the load of rolling elements, which must lead to lower durability of bearing compared to the situation before the preload use.

Despite the very important role of primary arteries and transportation network in providing relief for regions affected by an earthquake and black spots, they have received less attention. Therefore, in the current study, at first, the status quo of the traffic black spots and safe regions was identified to predict the movement direction, evacuation of residents from their habitat and temporary residence using the region zoning. The trips were assigned to the network based on the trip distribution matrix and their relevant travel times both related to the crisis state. The results indicated that out of 94 traffic regions, located in the area under investigation, 7 regions were put in the very low risk or safe regions group and 10 traffic regions were put in a very high-risk group. Additionally, the results indicated that out of 794 links, located in the area under investigation, about 32 links will have a very undesirable status following an earthquake.

Nowadays, in all the cities, there is an acute problem of a lack of parking spaces. The number of vehicles are becoming more and more larger, not only in megacities, but in small cities of the country, as well and there are no more parking places - the pace of solving the problem is several times slower than the rate of the transport growth among the citizens. The article is dedicated to the determination of the optimum sizes parking place for designing vehicles on a parking space, which is an element of the roads. The optimum amount parking places are determined on examples of the passenger cars and trucks. The results of research on dimensioning of parking spaces and recommendations to use the results for design of objects of transportation infrastructure are presented. According to the research, authors included the term "design vehicle" and gave its definition. The authors developed a template for 7 types of design vehicles and their sizes and also recommended sizes for longitudinal parking for each of their design vehicles. The optimum parking plot angles are determined, as well.

The aim of the article was to present the characteristics of conducting bathymetric measurements of a water area by means of a manned watercraft. The survey was performed in a body of water that is relatively shallow and frequently used by water sports enthusiasts. The results of the study described the shape of the bottom of the marina studied and identified dangerous places for vehicles moving on it. It was proved that using a manned vessel is dangerous or impossible to make measurements near the pier where the yachts were moored and areas where the depth was less than 1 meter. Using the points recorded by the Lowrance HDS Carbon 9 echo sounder, the authors of this paper generated 2D and 3D maps of the measured reservoir with the depths plotted on them. The created studies can be used when developing navigational aids to facilitate the driving of water vehicles.

This paper presents an analysis of the strength of a prototype test rig for testing rotors of unmanned aerial vehicles. Digital design software was used for the design work that covered the creation of a virtual model of the test rig and strength analysis of its key elements. The paper discusses the test rig solutions, applied to date, of the small main rotor research. From the assumed operational parameters and structural parameters of the rotor, the main forces acting on the designed structure were determined: lifting force, reaction torque and empty mass of the test rig. Suitable actuators of the control system enabling the regulation of the total pitch and periodic pitch of the rotor, within the full range of the angle of attack, were selected for the rotor under test. The FEM (Finite Element Method) strength analysis was carried out for the proposed support structure and the correctness of the design was verified.

This article considers the trunk lines, connected with the feeder region as the external environment for the system - feeder lines (its subsystems are container flows, ports and container ships). Hub ports are considered to be the boundary of the system and the external environment. Thus, mathematical models were simulated for the two levels. At the first level, container flows are determined (based on statistical data), which enter and exit the hub. At the second level, the mathematical model allows to find for the feeder line: volumes of container flows, the total capacity of the ships which serves the cargo, and parts of the distribution of this capacity between feeder ports.

A promising type of cargo vehicles are mobile ropeways formed by autonomous self-propelled rope units connected by a common cable transport system. The article presents a method for predicting the kinetics of the reliability indicators of the ropeway as a whole, individual rope units and their subsystems, taking into account the timing and volume of planned repairs. This method is advisable to use at the design stage of rope units, as it allows one to simulate the stage of their operation and provide the required level of reliability based on proactive replacement of structural elements that have reached the maximum permissible probability of critical failure. The method makes it possible to solve a number of important technical and economic problems related to operation of units and ropeways, including the development of an optimal strategy for their planned repairs, which has a minimum cost.

The analysis of traffic problems in large urban centers often requires the use of computational tools, which give the possibility to make a more detailed analysis of the issue, suggest solutions, predict behaviors and, above all, support efficient decision-making. Transport microsimulation software programs are a handy set of tools for this type of analysis. This research paper shows a case study where functions and limitations of Aimsun version 8.2.0, a commercial-like European software and Sumo version 1.3.1, a European open-source software, are presented. The input and output data are similar in both software and the interpretation of results is quite intuitive for both, as well. However, Aimsun's graphical interface interprets results more user-friendly, because Sumo is an open-access software presented as an effective alternative tool for transport modeling.

The paper is devoted to research of the impact of gradual liberalization of aviation market on the country's air transport industry development and on formation of external economic components of the country's GDP connected to it directly: export and import of air transport services. The study of the relationship between the operation indicators of air transport and formed external economic effects has been conducted using comparative, correlative and regression analysis based on the statistical data of Ukraine, which has its own air transport industry and is on the path of aviation liberalization. A strong dependence of the export of air transport services on the total number of international flights and its passengers was revealed. This determines the feasibility of tracking the external economic effects in the design of changes on directions and means of further development of country's air transport sector.

Container ships represent the fastest growing segment of maritime transport. The need to reduce unit transportation costs and environmental impact has led to development of the most capacious ultra-large container ships operating on the world's major shipping routes. A representative database of ultra-large container ships was created and further subdivided according to the main technical parameters. Using a simple cubic regression model, based on the least squares method, an equation, compliant to the general propeller law, was developed to predict the propulsion power of ultra-large container ships as a function of their sailing speed. The results obtained using the developed equation should be sufficiently close to the results of the exact verification calculations at the technical design stage. Then this prediction would find application in the design of both main propulsion, as well as waste heat and cold recovery systems.

Models developed in Highway Capacity Manual (HCM) are not suitable to cater to the effects of mixed traffic conditions and hence, its use is unjustifiable. This research investigates such a challenging problem as the effect of undesignated pedestrian crossings on the entry capacity of roundabouts. For the present study, field survey data were collected using video cameras from three roundabouts such that the base section (roundabout without pedestrian influence) and non-base sections (with pedestrian influence), both scenarios, were captured. A modified HCM equation was developed to estimate entry capacity and further, the reduction in capacity with respect to pedestrian volume is determined. Lastly, a relationship was developed to check the effect of pedestrian crossflow on the entry capacity. The relation shows that capacity reduced to 1841 Passenger Car Unit (PCU/h) when the pedestrian flow increased to 288 pedestrians/hour.

Growing environmental concern prompts vehicle users to search for cleaner and ecological transport modes. Many consumers and organizations have decided to replace conventional diesel or gasoline powered vehicles with alternative drive or alternative-powered vehicles. Operating conditions may have a heavy influence on the operating parameters of vehicles, such as: airpollution emission, energy consumption and fuel consumption. This paper presents a comparative analysis of the life cycle of conventional and hybrid drive vehicles in various driving conditions. The presented LCA results show that replacing a conventional diesel or gasoline vehicle with a hybrid electric drive vehicle results in approximately 40 % lower total lifetime air-pollutant emissions than those of conventional drive vehicles in urban driving conditions.

The COVID-19 pandemic has significantly affected the development of road transport, not only in Poland, but also worldwide. Limited mobility, especially at the beginning of the pandemic, had a large impact on the number of road accidents. The aim of the present study is to predict the number of road accidents in Poland and to assess the impact of the COVID-19 pandemic on variability of the number of road accidents. To attain the objective, annual data on the road accidents for every province in Poland were collected and analysed. Based on historical crash data, obtained from the police, the number of road accidents was forecasted for both pandemic and non-pandemic scenarios. Selected time series models and exponential models were used to forecast the number of accidents.

The paper deals with the influence of physical-metallurgical factors on resistance of the X52 and X70 steels in accordance with API 5L to sulphide stress cracking. The resistance against this kind of damage is relatively clearly claimed by usually used approach in this field by the tensile strength of steel, its hardness level, respectively. However, the experimental results had shown that the microstructural parameters are also the significant factors, which affect the resistance of steels to sulphide stress cracking. It was found that the quenching and tempering can significantly increase the resistance to sulphide cracking as in the case of hydrogen induced cracking. It would be appropriate to re-evaluate the material selection process that recommends to use the steels not exceeding approved strength limit in a case of the sulfane environments where the risk of the sulphide stress cracking exists.

The purpose of this paper was to determine the usability of unmanned hydrographic drones and photogrammetric techniques during the conduct of work, the results of which are potentially to serve as navigational materials in areas that, due to their characteristics, make it impossible to carry out research using crew vessels and direct shoreline determination. In order to prepare and carry out the measurement campaign with the greatest possible accuracy and safety, the authors of the article decided to determine the shoreline of the analyzed reservoir using photogrammetric methods. The use of satellite images allowed the border between land and water to be identified as precisely as possible, which had a direct impact on the accuracy of relating depth data to their location on Earth's globe. Use of unmanned vessels and orthophotos can find practical application when navigating vessels during maneuvers required high precision.

The purpose of this study was to improve the diagnostics efficiency of modern diesel engine injectors with electronic controls. Experimental studies, performed using certified specialized equipment of injectors' manufacturers and standard software packages for data analysis, made it possible to prove adequacy of theoretical research and get results that are more accurate. Those results contribute to development of a software product that allows identifying a particular faulty element during the defective injector's operation by using mathematical processing of the diagnostic data obtained when testing the injector. Thus, the time spent to repair the fuel injection system reduces. The developed software product also helps to predict the remaining injector's operational life and prevent possible technical failures during operation.

Air transport industry is one the many sectors significantly impacted by the COVID-19 pandemic. Travel restrictions and bans resulted in reduction in aircraft operation. Airlines have no option than to limit their services by grounding their fleet: as of April 2020, out of 22,000 passenger aircraft around the world, almost 14,400 were grounded [1]. Airport operators are trying to accommodate most of the grounded aircraft by utilizing their main operational space as aprons, taxiways and runways. The limited space at airports often means that aircraft have to be parked in non-standard positions, which may affect the airport daily operations. While planning aircraft parking, safety is the top priority. The effect of long-term load was not considered in the pavement design and could result in increased pavement maintenance requirements. Airport operators must also reflect aircraft maintenance needs in terms of engines, hydraulics, braking system, cabin interior and others.

The purchase decisions require information on where each phase in aretail supply chain should be placed. The presented method is an integrated tool for retail supply chain totransaction cost optimization. The model does not only present a company-level lean management's decisions within a supply chain, but it also shows the exact method to optimize the supply chain competitiveness. The allocation model also illustrates how the purchase decisions are allocated for producer, distributor and retail companies. The complexity of the allocation model may be affected by the size of the logistic costs, the algorithm used to calculate the supply chain purchase decisions and the final needs of the customers. The lean management approach could be a redemption to a company, but the results do not help to enhance competitiveness for the whole supply chain in every case. In this paper, a model method is demonstrated that helps to gain benefit of the lowest cost of integrated inventory management decisions. One of the essential parts ofthis research is that not onlythe lean management' result is considered, but effects of purchase decisions are integrated into the whole retail supply chain, as well. This type ofintegrated approachcan have an exponential impact on profitability on supply chain level effectiveness. In the paper are discussed issues that are important from the perspective of carriers, truck owners and operators, transportation policy makers and shippers. Different capacities of transportation and their costs and performance characteristics from lean aspect are discussed as well.

Intelligent transportation systems (ITS) are a today´s hot topic, especially in the context of the development of information technologies, which can be employed in transportation. Although the scope and the technical solution of these systems may vary, they are frequently based on VANET (Vehicular ad hoc network), i.e. a communication network, which is primarily generated among the moving subjects, which form ITS. Given the highly dynamic VANET, the questions are raised as to the data transmission. This paper is aimed to make a detail analysis of the communications within VANET using the simulation model, which includes the static infrastructure of ITS and to experimentally verify the impact of this infrastructure on the dynamics of information spreading in ITS. The authors present the results obtained from a few different scenarios, which have been tested.