Showing papers in "Archives of Transport in 2022"

Analysis of the operation states of internal combustion engine in the Real Driving Emissions test

Abstract: Internal combustion engines represent the largest share of motor vehicle propulsion types. Despite the introduction of alternative drives (hybrid and electric), combustion engines will continue to be the main factor in the development of transport. Therefore, work related to their technological development and reduction of their harmful effects on human health and the environment is required. The development of internal combustion engines can be seen in two directions: technological changes resulting in increased efficiency of such engines and the second direction connected with limi-tation of exhaust gas emission. The present work is included in the second direction of research interests and concerns the analysis of various operating conditions of internal combustion engines. The operating states, both static and dynamic, determine the operational properties of internal combustion engines, such as fuel and energy consumption as well as pollutant emissions. So far, such operating conditions have only been mapped on a chassis dynamometer in various homologation tests. The course of the type approval test was known and the conditions of measurement were also known, which made it impossible to introduce a random factor into such tests. Currently, these properties are determined in tests performed in real vehicle operating conditions – RDE (Real Driving Emissions). Such tests are representing real operating conditions of motor vehicles. Limitations for performing tests in real traffic conditions are, apart from formal requirements concerning the duration and distance of individual parts, the dynamic conditions of vehicles determined by the speed and acceleration of the vehicle. The study analyzed the properties of vehicle speed processes and engine operating states in the RDE test, taking into account its individual phases – driving in urban, rural and motorway conditions. Engine operation states are the processes of the engine rotational speed and its rela-tive torque. It was found that the dynamic properties of the vehicle speed process are much more significant than the engine operating states. It was also found that the road emission of pollutants in the RDE test, which is the property of vehicles measured in the test, the motorway phase properties have greatest impact.

Assessment of vehicle emissions at roundabouts: a comparative study of PEMS data and microscale emission model

Abstract: Energy efficiency has a central role to play in achieving decarbonisation targets in the transport system by changing the demand for mobility (eg. by influencing on peoples behaviors) and improving the performance of the fleet. In recent years there has been an increase of use of private transport, partly due to the recent pandemic and the reduced choice of public transport. People's travel habits have changed in frequency and motivation due to the reduced number of seats on public transport, due to social distancing but also due to online education and teleworking. This increase of use private cars has led to an increase in environmental emissions as a result of the high proportion of vehicles with combustion engines in urban areas. The highest concentrations have been recorded at road intersections and in par-ticular at roundabout configurations where there is a higher number of stop-and-go's overall. The increasing im-portance of air pollution from vehicle traffic has suggested that environmental considerations should be added to these aspects as a criterion for intersection design. Several studies in the literature analyze the environmental emissions generated by vehicle traffic using different methods such as on-site recording, mathematical modeling of dispersion phenomena, micro-simulation of vehicle traffic, use of appropriately equipped vehicles with sensors. This paper pre-sents a comparison between the results obtained from the Portable Emission Measurement System (PEMS) and the results obtained from the VERSIT+ emission model. Specifically, using a Portable Emission Measurement Systems (PEMS) installed on a series of test cars, instantaneous CO2 and NOX emissions were measured on repeated trips along two-lane roundabout intersections. The study was carried out by examining a selected two-lane roundabout in the city of Rzeszow (Poland) using 9 different vehicles fueled by petrol, diesel, and LPG. The results show that the investigated VERSIT+ emission model used led to an inaccuracies in the calculation of CO2 and NOx emissions. Furthermore, cur-rent micro-scale emission models may not estimate emissions of harmful exhaust components with sufficient accuracy due to the specificities of roundabout driving. Therefore, there is a strong demand for the development of new emission models, adapted to the driving behavior of drivers appropriate for different infrastructure objects such as roundabouts.

Comprehensive service quality evaluation of public transit based on extension cloud model

Abstract: Prioritizing the development of public transit and enhancing its attractiveness is an important way to solve the problem of urban traffic congestion and achieve sustainable development. To improve the service quality and overall opera-tional efficiency of urban public transit, an evaluation index system related to the comprehensive experience of pas-sengers, service supply quality of public transit enterprises, and supervision of management departments was intro-duced from both the demand and the supply of public transit travel services. Based on the data distribution characteris-tics of the boxplot in statistics, the evaluation level and corresponding value range of each index were determined, and the comprehensive weight of the index was determined using the linear weighting method combining the analytic hierarchy process and the entropy weight method, so as to reduce the influence of single weighting method on the evaluation results of comprehensive service quality of public transit. An evaluation method of public transit compre-hensive service quality based on the extension cloud model was established. The evaluation results of the model were obtained by calculating the cloud affiliation and comprehensive certainty, and a reliability factor was used to test the evaluation results, which solved the problem of randomness and fuzziness in the process of comprehensive service quality evaluation of public transportation and made the evaluation results closer to the reality. Finally, the estab-lished comprehensive evaluation model was applied to a city for example analysis, and the corresponding evaluation level was obtained as good. The value of the reliability factor in the model was less than 0.01, indicating that the model has good applicability and a certain application value for the comprehensive service quality evaluation of public transit. The evaluation method fully considered a variety of evaluation indicators, specified the evaluation level of comprehensive service quality of public transit, and the evaluation results provide a theoretical basis for public transport enterprise to make targeted improvement measures.

Fuzzy logic as a decision-making support tool in planning transport development

Abstract: Deliberations on transport development indicate that planning is its most significant aspect. One of the key issues in planning is selecting infrastructure projects for completion that will contribute to achieving the development objectives. The important functions of planning, as well as its complexity, indicate the need to use solutions in the decision-making support field. In Poland, in the area of strategic planning of infrastructure development, methods of supporting decision-making aimed at selecting infrastructure projects, taking into account their degree of compliance with strategic goals, are currently not applied comprehensively. The paper aims to address this gap with MCDA solution basing on review of literature combined with the authors’ experience in transport planning. Therefore, authors presented a proposed tool for supporting decision-making in planning transport development on a strategic level. The presented method allows for assessing infrastructure development projects in road and rail transport. Such assessments take into account a number of criteria corresponding to the main development directions, i.e. sustainable development and quality of life. Due to the method of formulating development objectives, it has been decided that it will be advantageous to apply fuzzy logic, which enables using natural language in decision-making support systems. To allow practical application of fuzzy logic, the Fuzzy Logic Toolbox package available in the MATLAB environment has been employed. The developed model contains a structure along with defined linguistic variables reflecting the decision-making criteria; also, it includes membership functions, inference rules as well as assessment results. The paper also defines the algorithm of decision-making support procedure. For verification purposes, the decision support model was applied in several real-life project evaluation cases, including a variety of projects in construction, development, and renovation of rail and road infrastructure. The deliberations described in this paper indicate the usefulness of fuzzy logic for supporting decision-making in planning transport development. It’s beneficial that the defined criteria can be applied in the case of projects in early preparation phase, enabling their practical application. Implementation of the solution in the MATLAB Fuzzy Logic Toolbox enables achieving fast results of the assessment of decision-maker preference level.

Vibration-based identification of engine valve clearance using a convolutional neural network

Abstract: Contemporary operation-related requirements for combustion engines force the necessity of ongoing assessment of their in operation technical condition (e.g. marine engines). The engine efficiency and durability depend on a variety of parameters. One of them is valve clearance. As has been proven in the paper, the assessment of the valve clearance can be based on vibration signals, which is not a problem in terms of signal measurement and processing and is not invasive into the engine structure. The authors described the experimental research aiming at providing information necessary to develop and validate the proposed method. Active experiments were used with the task of valve clearance and registration of vibrations using a three-axis transducer placed on the engine cylinder head. The tests were carried out during various operating conditions of the engine set by 5 rotational speeds and 5 load conditions. In order to extract the training examples, fragments of the signal related to the closing of individual valves were divided into 11 shorter portions. From each of them, an effective value of the signal was determined. Obtained total 32054 training vectors for each valve related to 4 classes of valve clearance including very sensitive clearance above 0.8 mm associat-ed with high dynamic interactions in cylinder head. In the paper, the authors propose to use a convolutional network CNN to assess the correct engine valve clearance. The obtained results were compared with other methods of machine learning (pattern recognition network, random forest). Finally, using CNN the valve clearance class identification error was less than 1% for the intake valve and less than 3.5% for the exhaust valve. Developed method replaces the existing standard methods based on FFT and STFT combined with regression calculation where approximation error is up to 10%. Such results are more useful for further studies related not only to classification, but also to the prediction of the valve clearance condition in real engine operations.

Effect of uniform time on the transmission of signals in rail open systems

Abstract: Railroads and the Rail Traffic Control Systems installed on them in Poland have recently been undergoing rapid technological development (Brodzik, 2019). Modern transportation solutions are susceptible to electromagnetic interference (Paś and Rosiński, 2017). Development of modern railroad infrastructure means not only stations and modern rolling stock, but also safe and reliable train traffic control systems based on the latest telecommunication and IT technologies (Ciszewski et al., 2017). In the last century these technologies were still considered dangerous and were introduced with great fear. Today, computerized systems for controlling railway traffic on the track are becoming the norm. Systems are created as "overlays" for existing relay systems or autonomous systems are built based on microprocessor systems (Burdzik et al., 2017). Today it is hard to imagine a modern control room without computer equipment. The introduction of microprocessor technology to railroad traffic control devices took place at the turn of the century. However, the use of modern radio systems in rail transport is the moment when technology based on the appeared in the world LTE (Long-Term evolution) standard. The development of modern data transmission technologies is integrally connected with the mobility of its users. In the presented article the author has tried to determine the impact of transmission synchronization on the basic transmission parameters of LTE signal (Chrzan, 2021). The convenience of using rail communications for its users is the possibility of uninterrupted access to data transmission services along the entire route of the train. Therefore, the research presented in this article was focused on the use of the public radio communication network for passenger data transmission and data transmission for railroad needs. The article presents the influence of synchronisation of data transmission in open railway systems using GPS (Global Positioning System) technology. It presents a description of the physical phenomena associated with synchronisation, and presents the author's method for carrying out measurements on railway line No. 4. For this purpose, a diagnostic station was built and special software for data transmission encryption was prepared. The process of synchronisation of clocks with the use of uniform time was adopted as the basis. General measurement results and conclusions resulting from the use of open transmission in railway radiocommunication systems synchronised by the GPS system signal are presented.

Spatiotemporal attention mechanism-based multistep traffic volume prediction model for highway toll stations

Abstract: As the fundamental part of other Intelligent Transportation Systems (ITS) applications, short-term traffic volume prediction plays an important role in various intelligent transportation tasks, such as traffic management, traffic signal control and route planning. Although Neural-network-based traffic prediction methods can produce good results, most of the models can’t be explained in an intuitive way. In this paper, we not only proposed a model that increase the short-term prediction accuracy of the traffic volume, but also improved the interpretability of the model by analyzing the internal attention score learnt by the model. we propose a spatiotemporal attention mechanism-based multistep traffic volume prediction model (SAMM). Inside the model, an LSTM-based Encoder-Decoder network with a hybrid attention mechanism is introduced, which consists of spatial attention and temporal attention. In the first level, the local and global spatial attention mechanisms considering the micro traffic evolution and macro pattern similarity, respectively, are applied to capture and amplify the features from the highly correlated entrance stations. In the second level, a temporal attention mechanism is employed to amplify the features from the time steps captured as contributing more to the future exit volume. Considering the time-dependent characteristics and the continuity of the recent evolutionary traffic volume trend, the timestamp features and historical exit volume series of target stations are included as the external inputs. An experiment is conducted using data from the highway toll collection system of Guangdong Province, China. By extracting and analyzing the weights of the spatial and temporal attention layers, the contributions of the intermediate parameters are revealed and explained with knowledge acquired by historical statistics. The results show that the proposed model outperforms the state-of-the-art model by 29.51% in terms of MSE, 13.93% in terms of MAE, and 5.69% in terms of MAPE. The effectiveness of the Encoder-Decoder framework and the attention mechanism are also verified.

Efficiency of energy storage control in the electric transport systems

Abstract: The problems of storage and supplying the energy, together with reducing energy intensity for transport, are now crucial for developing sustainable and reliable transport systems. The energy network must be gradually adapted to new loads and power consumption patterns, especially in railways. The article aims to develop the simulation model to investigate the energy storage systems in its use in the electric transport infrastructure. The authors review selected technical solutions for electric energy storage in transport. The theoretical aspects of energy exchange in the energy storage systems were presented as a base for a continuous simulation model of electric transport power supply. In the non-periodic random voltage input applied to the storage unit, it is pro-posed to use the calculation method based on the Duamel integral to analyze its charge-discharge processes. The resistance functions were applied to analyze the traction power supply mode with variable in time and space by active loads. The simulation showed that the direct connection of the unit to the traction network significantly reduces the traction energy consumption.

Modeling the designs in terms of logistics service center placement: a case study

Abstract: Suggesting the proper location for logistics facility can be considered as a decision making problem, wherein the final solution/decision is affected by multiple external or even internal circumstances. In order to address the decision making issues, various multi-criteria decision making (MCDM) techniques may be implemented; and hence, they can be applied even when making a decision about an adequate logistics service center (LSC) placement in an examined territory (i.e., national logistics network of the selected territory), which is an aim of this manuscript. Following the statements above, as for the individual instruments of MCDM to be implemented in terms of the crucial objective of this research, the definite decision making process will be carried out by applying the Analytic Hierarchy Process (AHP) followed by the Technique for Order Preference by Similarity to the Ideal Solution (TOPSIS), on the basis of criteria weights defined by the Saaty pairwise comparison method. The methods used appear to be ideal instruments towards decision making on the most suitable location which is represented by the region in our case. Subsequently, these will be ordered from the most preferred to least one by using a preference ranking. As a result of the application of AHP and TOPSIS approaches, based on the conducted calculations in regard to decision making on identifying the proper LSC location out of eight selected regions, one specific region will be defined as the most suitable (so-called compromise) scenario. Individual tools allow for reducing the number of assigned criteria that are taken into account in searching process for individual solutions. In order to objectify the entire decision making procedure, ten topic-involved experts having practical experience with a subject of logistics object allocation will be asked to participate in the process. Preferences differ from one decision maker (expert) to another; hence, the outcome depends on who is making decisions and what their goals and preferences are.

Quantitative safety analysis of train control system based on statatistical model checking

Abstract: With the rapid development of communication technology, the Train-centric Communication-based Train Control (TcCBTC) system adopting the train-train communication mode to reduce the transmission link of control information, will become the direction of urban rail transit field development. At present, TcCBTC system is in the stage of key technology research and prototype development. Uncertain behavior in the process of system operation may lead to operation accidents. Therefore, before the system is put into use, it must undergo strict testing and security verification to ensure the safe and efficient operation of the system. In the paper, the formal modeling and quantitative analysis of train tracking operation under moving block are carried out. Firstly, the structure of TcCBTC system and the train tracking interval control strategy under moving block conditions are analyzed. The subsystem involved in train tracking and the uncertain factors in system operation are determined. Then, based on the Stochastic Hybrid Automata (SHA), a network of SHA model of train dynamics model, communication components and on-board controller in the process of train tracking is established, which can formally describe the uncertain environment in the process of system operation. UPPAAL-SMC is used to simulate the change curve of train position and speed during tracking, it is verified that the model meets the safety requirements in static environment. Finally, taking Statistical Model Checking (SMC) as the basis of safety analysis, the probability of train collision in uncertain environment is calculated. The results show that after accurately modeling the train tracking operation control mechanism through network of SHA, the SMC method can accurately calculate the probability of train rear end collision, which proves that the method has strong feasibility and effectiveness. Formal modeling and analysis of safety-critical system is very important, which enables designers to grasp the hidden dangers of the system in the design stage and safety evaluation stage of train control system, and further provides theoretical reference for the subsequent TcCBTC system design and development, practical application and related specification improvement.

The use of the risk matrix method for assessing the risk of implementing rail freight services

Abstract: The article presents a proposal for the use of a risk matrix for assessing the safety of the implementation of rail freight transport. The starting point for considerations related to risk assessment is the conditions arising from the business need and the obligation of entities operating in the railway market to ensure the safety of the implementation of freight tasks. The authors presented selected literature within the framework of the issues discussed. The layers of risk assessment, which include the analytical layer, the decision layer and the elimination layer, indicate the possibility of considering the problem of risk assessment from different perspectives. The identification of direct causes and consequences of undesirable events during the implementation of rail freight transport was also made. The article describes one of the methods of risk management which is the risk matrix. The authors stressed that the construction of a risk matrix should be preceded by an analysis of the factors that affect the safety of rail transportation. This is possible by determining their probability of occurrence and setting values for the consequences of adverse events. The article divides the assignment of levels of adverse events to a five-level risk matrix (slight, low, medium, high, very high). Also presented is a case study considering the risk assessment of rail freight transport in Poland using the risk matrix method for railway accidents in the area of railway lines. Thanks to the development of the risk matrix, a risk management strategy can be used. The last part of the article is a summary, which highlights the possibility of applying the presented approach to risk assessment among entities operating in the rail transport market.

Shifting the population mobility of the Ukraine western region on the strength of the COVID-19 pandemic

Abstract: The Covid-19 pandemic has significantly affected the economic and social spheres of all countries. Restrictions intro-duced to reduce the risk of transmission have changed the structure of population movements. The impact of these restrictions on the characteristics of intercity travel is still an understudied problem. Based on the analysis of statisti-cal data and the results of questionnaires, the article assesses the impact of pandemic restrictions on population mobil-ity in the Western region of Ukraine and changes in the distribution of passenger flows between different modes (bus, rail, private transport, joint travel). In 2020, the volume of passenger traffic in the region decreased by an average of half compared to the previous year. The decline is sharper for rail passenger transport compared to the bus transport. For more developed railway networks, the impact of the pandemic on passenger traffic is more pronounced. Quarantine restrictions have also increased the share of own car travel. According to research, the distribution of intercity trips between modes is influenced by the age and sex of the traveler. During the pandemic, users of transport services who travel with children under the age of 14 choose private transport to travel more often than those who travel alone. The degree of influence of the above factors on the distribution of modes depends on the length of the trip. The application part of the work presents the results of modeling passenger flows of the studied region in the software environment PTV Visum. It was found that at the beginning of the quarantine restrictions the number of intercity trips decreases sharply. As the duration of restrictions increases, the rate of decline in mobility decreases. These data can be further taken into account when planning the work of transport enterprises and meeting the population`s demand for travel. The practi-cal application of the study results is that the identification of trends in the mobility of residents of the studying region depending on the impact of pandemic restrictions allows you to predict the mode and type of vehicles used. Based on these data, you can determine marketing strategies for the development of certain modes and directions of transporta-tion.

Assessment of ship manoeuvring safety in waterway systems by relative navigational risk

Abstract: The safety of vessels navigating in the sea waterway system is ensured by fulfilling the acceptable restrictions called safe ship operation conditions in that system. The assessment of navigation safety is particularly important when the conditions for safe operation of ships in the waterway system are changed concerns increasing the maximum parameters of vessels, increasing the allowable hydrometeorological conditions or changing the minimum tug assistance. The article presents a method for assessing navigation safety when the conditions for the safe operation of vessels in the waterway system get changed. The method uses two indicators, which are difference in navigation risks and relative navigation risk. To determine the navigational risk, algorithms were developed for calculating the probability of accidents caused by the deterioration of navigation conditions and technical failure of ship equipment and tugs. Another algorithm was developed for calculating the consequences of the accidents that involve blocking a waterway by a ship anchoring in an emergency, grounding, impact of the ship against a port structure or moored ship and a collision with another ship in motion. The method developed for assessing navigation safety by means of relative navigation risk can be used in practice when changing the conditions for safe operation of vessels in the waterway system and when the system is modernized. Navigational safety management is a decision process that is implemented in the loop presented in the article. The acceptable risk is determined on the basis of vessel traffic intensity and ship parameters defined by safe operation conditions for a given waterway system. Relative navigational risk may be used in assessment and comparison of various conditions of safe ship operation. The probability of an accident caused by ship's moving outside the available navigable area due to technical failures of ship equipment or tugs is determined, depending on the type of port waterway and the manoeuvres performed.

An analysis of influential factors associated with rural crashes in a developing country: A case study of Iran

Abstract: Road traffic deaths continue to rise, reaching 1.35 million in recent years. Road traffic injuries are the eighth leading cause of death for people of all ages. Note that there is a wide difference in the crash rate between developed and developing countries and that developed countries report much lower crash rates than developing and underdeveloped countries. World Health Organization reports that over 80% of fatal road crashes occur in developing countries, while developed countries account for about 7% of the total. The rate of road crashes in developing countries is higher than the global average, despite some measures reducing deaths over the last decade. Numerous studies have been carried out on the safety of urban roads. However, comprehensive research evaluating influential factors associated with rural crashes in developing countries is still neglected. Therefore, it is crucial to understand how factors influence the severi-ty of rural road crashes. In the present study, rural roads in Mazandaran province were considered a case study. The Crash data collected from the Iranian Legal Medicine Organization covers 2018 to 2021, including 2047 rural crash-es. Dependent variables were classified as damage crashes and injury-fatal crashes. Besides, independent variables such as driver specifications, crash specifications, environment specifications, traffic specifications, and geometrical road specifications were considered parameters. The logit model data indicate that factors associated with driver and crash specifications influence rural crashes. The type of crashes is the most critical factor influencing the severity of crashes, on which the fatal rate depends. The findings suggested that implementing solutions that minimize the effect of the factors associated with injury and death on rural roads can reduce the severity of crashes on rural roads that share the same safety issues as the case study. Further studies can also be conducted on the safety and mechanics of the vehicle by focusing the research on the types of vehicles and the sources of the damage.

Impacts from transportation measures in national appraisal guidelines: coverage and practices

Abstract: Transportation appraisal has a potential important role in prioritization of transportation investment projects and other transportation measures. Appraisal practices vary much over countries and time, but these differences are not fully known. More knowledge on the variation in practices may contribute to smoother knowledge exchange between countries and more informed choices in the further development of each national practice. In this paper, we present both an updated mapping and a meta-analysis of impact coverage in national appraisal guidelines for transportation measures and spatial measures more generally. Our updated mapping of impact coverage covers 18 national and regional guideline sets and 44 sorts of impact. It shows rather similar overall impact coverage in the reviewed guide-lines for economic, social and environmental impacts. The most advanced appraisal practices are found in Northern and Western Europe and Oceania. We find that supplementary quantitative analyses are most common for economic impacts, while multi-criteria analyses are most common for environmental impacts. Our meta-analysis covers ours and 15 earlier impact mappings, jointly covering 42 countries and regions. In this examination, we show how impact cover-age in appraisal practices has improved over time, particularly for environmental, user and wider economic impacts. The meta-analysis also reveals that Western and Northern European and Oceanian countries and dependencies have had the widest impact coverage from 1998 to 2020, both in CB and overall. To examine what characterize countries with broad and narrow impact coverage, we have applied econometric regression models that are linear (i.e. linear least squares), quasi-linear (i.e. Tobit) and fractional response-based (i.e. fractional probit and fractional logit). In these regression analyses, we control for study-specific characteristics and clustering the standard errors on countries. Our results show that the CB impact coverage tends to increase with economic wealth, equality and population size in developed countries, while we find no such patterns for overall impact coverage.

Influence of the type of place occupied by a tram passenger on the ride comfort

Abstract: In cities with developed transport infrastructure, many people use public transport in their everyday lives. In order for the passenger's journey to be comfortable and for the passenger to travel more willingly by tram than by car, many conditions must be met. A passenger must feel comfortable in a public transport vehicle, which includes, among others: appropriate temperature in the vehicle, no crowding, the possibility to seat, the possibility of a quick vehicle-change, short travel time, no noise and many others. A very important criterion from the point of view of travel comfort is also the level of vibrations in the tram. A tendency can be noticed that vehicles with a low vibration level are rated much higher by public transport passengers and citizens. Vibration itself can also be an indirect cause of noise. The greater the noise, the greater the dissatisfaction of the passenger which indicates the high role of vibrations as a factor of passenger satisfaction or dissatisfaction. The aim of the work is to test and evaluate the vibration level in the partially low-floor Moderus Beta MF 02 AC tram manufactured by the company Modertrans Poznań in Poland. Assessed was be the vibration comfort in selected points of the vehicle, including the floor and passenger seat. The level of vibrations in trams of the same type were compared. Due to the lack of specific Polish regulations regarding the permissible level of vibration in trams, an attempt was made to compare the obtained results with railway standards requirements or for-eign countries requirements. The study proved that the level of vibrations differs in trams belonging to the same type. Significant damping of vibrations in the vertical direction by the passenger seat was observed. Maximum level of vibrations in the passenger area of the vehicle was observed on the floor above the bogie. It was found when compar-ing the values of vibration accelerations and comfort indicators with railway standards - that the Moderus Beta tram on the reference section of the track could be considered as a very comfortable vehicle.

Modelling the costs of pre-hospital transport service for victims of road accidents in TDABC

Abstract: The pre-hospital transport of victims of road accidents in Morocco by basic ambulances concerns the majority of the population of victims requiring urgent care. It also constitutes the common service that benefits the entire population of victims, in terms of pre-hospital care. The objective of this contribution is to develop a model for calculating the costs of pre-hospital transport of road accident victims using Time-Driven Activity-Based Costing (TDABC). This model could be effective in better understanding how consumption occurs and how resources are administered and distribut-ed within the pre-hospital care service portfolio. The qualitative research approach that we have adopted in the con-text of this study has enabled us to map and identify all the activities and tasks carried out in the process of pre-hospital transport of road accident victims. The model obtained is flexible enough to adapt to the various situations of pre-hospital transport of road accident victims by basic ambulances. The application of this model in the Moroccan context, delimited in a well-defined round trip (civil protection - accident site - hospital - civil protection) demonstrates that the said model is valid for cost calculation. The calculations made (217.47 MAD, 224.31 MAD, 225.45 MAD and 226.59 MAD) allow us to identify the possible cases of victims transported by basic ambulance. However, the TDABC, applied to the pre-hospital transport of road accident victims, has some limitations, in particular the estimation of time which is the main key to the allocation of the consumed resources. The results show that the TDABC promotes a better knowledge of all the processes related to the pre-hospital transport service. It allows making visible the value of the costs of the victims of road accidents in the selected patient population. Indeed, when the model is used in the set of routes (black points), decision makers are able to see, on the one hand, the variation of costs between similar pre-hospital transport services and different routes for the same transport services and, on the other hand, the value of the costs of each category of road accident victims' population.

Evaluation of air traffic in the context of the Covid-19 pandemic

Abstract: The Covid-19 pandemic unexpectedly shook the entire global economy, causing it to destabilize over a long period of time. One of the sectors that was particularly hit hard was air traffic, and the changes that have taken place in it have been unmatched by any other crisis in history. The purpose of this article was to identify the time series describing the number of airline flights in Poland in the context of the Covid-19 pandemic. The article first presents selected statistics and indicators showing the situation of the global and domestic aviation market during the pandemic. Then, based on the data on the number of flights in Poland, the identification of the time series describing the number of flights by airlines was made. The discrete wavelet transformation (DWT) was used to determine the trend, while for periodicity verification, first statistical tests (Kruskal-Wallis test and Friedman test) and then spectral analysis were used. The confirmation of the existence of weekly seasonality allowed for the identification of the studied series as the sum of the previously determined trend and the seasonal component, as the mean value from the observations on a given day of the week. The proposed model was compared with the 7-order moving average model, as one of the most popular in the literature. As the obtained results showed, the model developed by the authors was better at identifying the studied series than the moving average. The errors were significantly lower, which made the presented solution more effective. This confirmed the validity of using wavelet analysis in the case of irregular behaviour of time series, and also showed that both spectral analysis and statistical tests (Kruskal-Walis and Fridman) proved successful in identifying the sea-sonal factor in the time series. The method used allowed for a satisfactory identification of the model for empirical data, however, it should be emphasized that the aviation services market is influenced by many variables and the fore-casts and scenarios created should be updated and modified on an ongoing basis.

Determination of Truck Maintenance Allocation Scheme Based on SA-GA

Abstract: As an important department of railway transportation and production, large freight train depot is responsible for the regular overhaul and maintenance of railway trucks. The shunting operation of freight train depot covers the whole process of railway trucks entering, storing, overhauling and leaving the depot. It is an important step in the implemen-tation of the maintenance operation. Usually, shunting personnel in the depot transport the trucks to be overhauled to the maintenance line by relying on the shunting operation plan, which is the key to determine the shunting operation plan according to the distribution relationship between vehicles and maintenance. Firstly, this paper analyzes the process of centralized shunting operation in the freight train depot and the factors affecting the time-consuming based on the research idea of flexible workshop scheduling problem. Then, on the premise that the proportion of the weight coefficient will have an impact on the time-consuming of truck busy and shunting in the shunting process, and with the goal of minimizing the time-consuming of truck maintenance busy and shunting, the allocation model between trucks and maintenance lines is established; In addition, an improved genetic algorithm is proposed to solve the established model; Finally, combined with the maintenance of railway trucks in a large freight train depot, an example analysis is carried out on this basis. The results demonstrate that using simulated annealing genetic algorithm to solve the model can obtain the allocation scheme between railway trucks and maintenance operation line. Under the influence of three different coefficients, compared with genetic algorithm, simulated annealing genetic algorithm can reduce the deten-tion time of railway trucks in depot by 0.21%, 0.09% and 0.12% respectively, which is beneficial to reducing the deten-tion time of maintenance vehicles in depot, It plays a positive role in improving the maintenance efficiency of trucks in the depot, and also provides new ideas for the research of railway truck shunting operation.

Model of operational planning of freight transportation by tram as part of a green logistics system

Abstract: The introduction of environmentally friendly technologies is becoming increasingly necessary to combat global warm-ing and air pollution in cities. The concept of eco-logistics is seen as an effective approach to the management of materials and related flows in order to reduce environmental and economic damage to the environment. The sustaina-ble development of green supply chains is based on the use of environmentally friendly types of vehicles, reduction of energy and other resources consumption, optimization of transport and technological processes in delivery systems. As part of the development of green supply chain, it is proposed to transport goods by freight trams, which eliminates the need for heavy trucks in the city, improves traffic conditions and reduces the environmental impact of transport. The research was conducted for the city of Poznan. The distribution system of the city of Poznan operates in conditions of stochastic demand for deliveries from clients and the risk of lack of sufficient supplies in distribution centers. To take into account the specificity of the distribution system of cargo delivery in conditions of uncertainty and risk, a simula-tion model of the organization of the material flows within the transport system of the city of Poznan has been pro-posed. The result of simulation is the optimal assignment of clients to the distribution centers, as well as the value of total mileage with the load, which is a random variable. It is assumed that the random variable is distributed according to the normal distribution law. The results were calculated and compared for two variants, i.e. for constant demand and sufficient quantity of cargo in distribution centers, and for variable demand and uncertainty conditions, e.g. insuffi-cient cargo quantity in distribution centers. The purpose of the paper is to develop a simulation model for planning supplies of small consignments of goods by trams implementing green logistics concept with variable demand for transportation. After a short introduction of the problem, the literature review related to the concept of green logistics and requirements of transport and distribution system are presented in section 2. In section 3, the research problem and research methodology are described. Section 4 provides the results of assignment of clients to distribution centers. The paper ends with concluding remarks.

Machine learning algorithms for the problem of optimizing the distribution of parcels in time-dependent networks: the case study

Abstract: In the paper we present machine learning algorithms for the problem of optimizing the distribution of parcels in sto-chastic time-dependent networks, which have been built as a part of some Distribution Optimization System. The prob-lem solved was a modified VRPTW (Vehicle Routing Problem with Time Windows) with many warehouses, a heteroge-neous fleet, travel times depending on the time of departure (stochastic time-dependent network) and an extensive cost function as an optimization criterion. To solve the problem a modified simulated annealing (SATM) algorithm has been proposed. The paper presents the results of the algorithm learning process: the calibration of input parameters and the study of the impact of parameters on the quality of the solution (calculation time, transport cost function value) de-pending on the type of input data. The idea is to divide the input data into classes according to a proposed classifica-tion rule and to propose several strategies for selecting the optimal set of calibration parameters. These strategies consist in solving some multi-criteria optimization tasks in which four criterion functions are used: the length of the designated routes, the computation time, the number of epochs used in the algorithm, the number of designated routes. The subproblem was building a network model of travel times that is used in constructed SATM algorithm to determine the travel time between recipients, depending on the time of departure from the start location. An attempt has been made to verify the research hypothesis that the time between two points can be estimated with sufficient accuracy depending on their geographical location and the time of departure (without reference to the micro-scale, i.e. the detailed structure of the road network). The research was conducted on two types of data for Warsaw: from transport companies and one of the Internet traffic data providers. Learning the network model of travel times has produced very promising results, which will be described in the paper.

Evaluation of the impact of COVID-19 pandemic on transportation: a case study of Iran

Abstract: Coronavirus first appeared in January 2020 and has spread dramatically in most parts of the world. In addition to exerting enormous impacts on public health and well-being, it has also affected a broad spectrum of industries and sectors, including transportation. Countries around the world have imposed restrictions on travel and participation in activities due to the outbreak of the virus. Many countries have adopted social distancing rules requiring people to maintain a safe distance. Therefore, the pandemic has accelerated the transition into a world in which online educa-tion, online shopping, and remote working are becoming increasingly prevalent. Every aspect of our life has witnessed a series of new rules, habits, and behaviours during this period, and our travel choices or behaviours are no exception. Some of these changes can be permanent or have long-lasting effects. To control this situation, these changes must first be recognised in various aspects of transportation in order to provide policies for similar situations in the future. In this regard, this study seeks to examine how transportation sectors have changed in the first waves of the pandemic. Iran has been selected as the case study in this paper. This research is divided into two parts. The first part focuses on the effects of the Coronavirus pandemic on rural transportation in Iran. This is followed by assessing the impacts of the virus on urban transportation in Tehran (the capital of Iran). The behaviour of more than 700 travellers in terms of trip purpose, travel time, and mode choice is evaluated using a questionnaire. Results indicate that the number of passen-gers has reduced dramatically in rural transportation systems. In such systems, considerations such as keeping social distancing, disinfection of passengers and their luggage, and unemployment of a group of personnel working in the transportation industry have been more evident. In urban transportation, education trips have dropped the most. This might relate to an increase in online teaching and health concerns. The same pattern can be seen in the passengers who used bicycles, public taxis, and other public transportation systems. Finally, during the pandemic, drivers’ speed has increased, which justifies the need for traffic calming for drivers.

Fuel Saving Indeks Assessment on Driving Behavior Control System Prototype Model Using Neural Network

Abstract: Efficient fuel consumption in the world is essential in automotive technology development due to the increase in vehicle usage and the decrease in global oil production. Several studies have been conducted to increase fuel consumption savings, Fuel Cells (FCs), the application of alternative energy vehicles and the Engine Control Unit (ECU) system. FCs do not require oil energy to propel the vehicle, so this technology promises to reduce energy consumption and emissions. However, this research still leaves problems. FCs are susceptible to short circuit hazards, and ownership costs are very high. Alternative energy applications produce less power, less responsive acceleration, and insufficient energy sources to enter mass production. The ECU application still has an orientation toward achieving stoichiometry values, so the increase in fuel efficiency has the potential to be improved. Driving behavior is a variable that has a close relationship with fuel consumption efficiency. However, research on driving behavior is only studied for implementation in autonomous car-following technologies, safety systems, charging needs characteristic of electric vehicles, emission controls, and display images on in-vehicle information systems. Meanwhile, research on driving behavior as a control system to improve fuel efficiency has not been carried out. To that end, this study proposes the use of driving behavior for a newly designed control system to improve fuel efficiency. The control system in this research is a prototype model to be assessed using the Fuel Saving Index (FSI) analysis. An artificial neural network is used to help the recognition of driving behavior. The results showed that the newly designed control system was categorized on scale IV of FSI. On this scale, the power generated by the engine is quite optimal when it is in the eco-scheme driving behavior. The driving behavior control system can significantly improve the efficiency of fuel consumption. Air to Fuel Ratio (AFR) is achieved above the stoichiometric value

Operational evaluation of atomization indicators for gasoline with admixtures of ethanol and butanol during Keep-Clean tests

Abstract: The global policy of reducing road transport sector pollution requires the introduction of significantly modified already in use technologies and construction solutions. Currently, direct fuel injection technology is the best solution in terms of reducing fuel consumption and exhaust emissions of standard pollutants into the atmosphere, as well as further improving the engine performance. In terms of exhaust emissions, direct injection spark ignition engines are characterized by significantly higher exhaust emissions of particulate matter (approximately 10 times higher) compared to indirect fuel injection SI engines, they show a greater tendency to knocking combustion and are prone to the formation of harmful deposits on engine parts, including in the fuel injectors. The injector tips located in the combustion chamber are exposed to the direct influence of the very high pressure and temperature caused by the combusting fuel-air mixture, which contributes to the rapid formation of harmful deposits. Operation-based injectors contamination in spark ignition engines results in a reduction of the cross-sectional flow diameter of the injector, which then necessitates the extension of the injection time in order to maintain the fuel dose and the expected engine operating parameters. The tests were carried out on an engine dynamometer and an optical test stand for fuel atomization process. The presented research analyzes indicate the possibility of using admixtures that effectively reduce the likelihood of contamination. The paper presents a results analysis of engine tests performed in accordance with the CEC F-113-KC procedure. Additionally, the injectors were tested to conduct an analysis of the injected fuel stream’s geometric indicators. The range, surface area and speed of the injected fuel stream as well as the fuel distribution in the stream were determined based on an equivalent indicator. The obtained results indicated that ethanol and butanol admixtures of 10% (V/V) to gasoline did not significantly extend the fuel injection time as compared to the reference fuel. A further increase in the proportion of ethanol caused a significant deterioration of the fuel flow and the geometric indicators of the fuel spray.

A Study on Two-stage Selection Model of Tourism Destination at the Scale of Urban Agglomerations

Abstract: Considering that the demand of tourism destination is variable on the scale of urban agglomeration, the selection process of travel destination is divided into two stages. The traditional transportation combination model based on the multinomial Logit cannot reflect this characteristic. And it is the lack of consideration of the influence of travel distribution and the dynamic transfer of passenger flow between various transport routes. Therefore, this thesis established a combination model of travel demand distribution and transportation assignment with two-stage terminal selection characteristics based on the nested Logit. Based on the analysis of tourists' trip process on the scale of urban agglomeration, a tourist flow transport network with travel destination nest structure is constructed. The generalized cost impedance function of transportation route is constructed based on the direct cost of transportation mode and the indirect cost of travel time. Based on the characteristics of two-stage destination selection of tourists, the form of travel distribution function of tourist flow is given. Through the first-order optimization conditions, it proved that the volume of travel distribution and tourism passenger transport assignment can meet the two-stage equilibrium conditions in the equilibrium state. Based on the idea of MSA algorithm, it designed the solution algorithm of the model and verified the feasibility of the model and algorithm in a simplified example. The calculation results show that the two-stage equilibrium assignment model proposed in this paper can obtain the volume of travel distribution and transportation assignment at the same time, meanwhile compared with the multinomial logit model, the nested Logit structure fully considers the attraction measure of the city destination and the scenic spot destination, which is more in line with the choice behavior of the tourists when choosing the transportation route. Thus, it provides a new comparable method for the optimal allocation of tourism passenger flow transport network resources on the scale of urban agglomeration, and can provide data support for the transportation organization plans of government decision-making departments and tourism transport enterprises.

Research on the site selection and path layout of the logistics distribution center of marine ships based on a mathematical model

Abstract: For logistics enterprises, site selection and path layout are related to the cost and efficiency of distribution, which is a very critical issue and has an important impact on the development of enterprises. Compared with land logistics, the cost of marine ship logistics is higher due to the high cost of ships, so the research on the location and path layout of its distribution centers is also particularly important. This paper established a two-layer model under the assumption that unit transportation costs and administration expenses are known for the site selection and path layout problems of marine ship logistics distribution centers. Corresponding constraint conditions were set. The upper layer was the optimization model of the site selection problem of the distribution center, and the objective function was to minimize operating and construction costs and was solved using the quantum particle swarm optimization (QPSO) algorithm. The lower layer was the optimization model of the distribution path layout, and the objective function was to minimize the logistics distribution cost and was solved using the ant colony optimization (ACO) algorithm. The model was veri-fied through an example analysis. It was assumed that there were three ships, five candidate distribution centers, and ten customer points. The model was solved in MATLAB software. The results of the example analysis showed that com-pared with K-means, genetic algorithm (GA), and particle swarm optimization (PSO)-ACO algorithms, the QPSO-ACO algorithm had the shortest running time, about 60 s, which saved about 50% compared to the K-means algorithm. The optimal cost of the QPSO-ACO algorithm was 293,400 yuan, which was significantly lower than the K-means, GA, and PSO-ACO algorithms (459,600 yuan, 398,300 yuan, and 357,700 yuan). In this example, the site obtained by the QPSO-ACO algorithm was distribution center 2, and the obtained path distribution was 1-7-5-4, 2-6-3, and 10-8-9. The results verify the effectiveness of the QPSO-ACO algorithm in solving the problem of site selection and path layout. The QPSO-ACO algorithm can be applied in the actual marine ship logistics.

The optimum strategy for mode choice modelling of interregional fish transport considering shippers' heterogeneity

Abstract: The determinants of mode choice of interregional transport of fish, which is highly perishable, vastly differ from that of other commodities. These determinants are to be identified to improve transport efficiency. A questionnaire survey of shippers is used to collect the data. Highly correlated observed variables are combined to form four latent factors by factor analysis to reduce the errors in modelling. Logical relations among the component variables of latent factors are perceived, and mathematical formulations are used to estimate new variables. It is found that transportation costs and shipment weight contributes to factor 1, while distance contributes to factor 2. However, transportation costs are associated with distance and shipment weight. Thus, the variable, transportation cost per q-km, is estimated. Survey respondents' attitudes are also incorporated into modelling by including qualitative factors obtained by the factor analysis of shippers' preference ratings. A latent class analysis confirmed the existence of heterogeneity among ship-pers. Misrepresentations of effects occur in modelling if the heterogeneity in the data is not considered. No studies have found the best combination of observed variables, latent factors, estimated variables, and qualitative factors, consider-ing shippers' heterogeneity in freight mode choice. Hence, this study is done to find the optimum modelling strategy. Modelling revealed that models built with estimated variables outperformed those built with latent factors. Including qualitative factors along with observed variables and estimated variables showed further improvement. However, the model that includes observed variables, estimated variables, and qualitative factors considering shippers' heterogenei-ty is the best. It was found that the mode selection behaviour of different latent classes of shippers is distinct. A mode shift from road to rail could be achieved by lowering transportation costs and increasing speed, reliability, and safety for fish transport. Expanding roll on–roll off facilities, dedicated freight corridors, parcel trains, refrigerated contain-ers, and piecemeal service by rail promote a mode shift from road to rail and reduce energy usage.

Product-Service System design – an example of the logistics industry

Abstract: Product-Service System (PSS) has been perceived since the 90s as a concept supporting enterprises of various indus-tries in creating a competitive advantage and generating new value for customers by expanding the offer with addi-tional services related to the product. Product-Service System (PSS) draws attention to the life cycle of products and services and the circular economy, which supports sustainable development. All the time, practitioners and theorists report the need to develop new Product-Service System (PSS) for other industries. Until now, a number of practical and methodological aspects related to design remain unresolved. The paper presents issues related to the Product-Service System (PSS) and PSS design. A literature review and gaps in available methods are presented. A conceptual frame-work for Product-Service System (PSS) design that has been used in the logistics industry is presented. By referring to the design of a selected process from the logistics industry, it was presented how to analyze the process during design and what methods of design support to use. Reference is made to mathematical modeling based on the optimization function and computer modeling with the use of a simulation model. Attention was also paid to the importance of knowledge of the industry and having expert knowledge about the designed processes in the systems. It is also extremely important to have the appropriate data set for a given case. In addition to the general mathematical and computer model, reference was also made to a chosen element of Product-Service System (PSS). The mathematical and simulation model included in the study refer to the process of completing customer orders in a logistics company. It is one of the most laborious and time-consuming processes. The FlexSim simulation environment was used to perform the computer simulation. A total of 15 variants were considered, which differ in terms of the scope of services provided during the process. The scope of services significantly affects the cost, time and profit. The purpose of the constructed model is to find a variant for the adopted data in which the profits will be maximized while maintaining the constraints imposed on the system.

E-bike use in urban commuting: empirical evidence from the home-work plan

Abstract: A substantial part of the environmental issues relies on fossil fuels. This dependence is crucial in transport even though many incentives and interventions have been proposed to reduce pollutant emissions. Electric vehicles with zero emissions might represent a viable solution in urban areas. Many cities encouraged modal shift policies from cars to an e-bike or car-sharing/pooling with electric vehicle fleets. This paper reports the ongoing outputs from a pilot project, relying on a modal shift to the e-bike, promoted in the city of Messina (Southern Italy) by the Ministry of Ecological Transition. The objective is to assess, in the territorial context of Messina, the e-bike as a competitive transport mode in terms of social awareness of eco-friendly mobility solutions. The available dataset consists of about nine months of observations; data on total distance and trips have been gathered for each e-bike. It emerged how, in a typical working day, the average distance travelled is about 6.9 km, the usage rate for working days is about 81 %, and the carbon dioxide reduction is about 245 kg per person each year. During the project, information was also collected on the satisfaction with the e-bike and the quality of travel. It emerged that regular bicycle use has good repercussions on the interviewees' psycho-physical well-being, reducing the stress factor connected with urban mobility. Despite mechanical breakdowns and the lack of an infrastructure dedicated to active mobility representing a limitation, travel comfort and safety are two latent variables that are transversally valid within the population; about 15 % became familiar with the e-bike and made it their primary mode choice for everyday activities. In this sense, outputs represent a starting point for future policies and give back adjustments before introducing similar services to students from the university and second-grade schools.

Modelling the acoustic signature and noise propagation of high speed railway vehicle

Abstract: The proportion of high speed railway vehicles in the rolling stock of national carriers providing public transport services is constantly increasing. Currently, Alstom vehicles run at the highest speed on railway lines in Poland. The paper attempts to identify the acoustic signature of high speed railway vehicles. There are many works and studies aimed at identifying or defining the acoustic signature of high speed railway vehicles. However, the authors of these works carried out their research in a rather narrow scope, i.e. the measurement cross-section had only 1 or 2 measure-ment points with one microphone at each point. As part of the conducted experimental research, the location of testing grounds was determined, the measurement apparatus was selected and the methodology for carrying out measurements including the assessment of noise emission on curve and straight line were specified for electric multiple units. The object of the tests were railway vehicles of Alstom company, type ETR610, series ED250, the so-called Pendolino, moving on a selected measuring route without stops at a speed of 200 km/h. Measurements were carried out on the railway line no. 4 Grodzisk Mazowiecki – Zawiercie, section Grodzisk Mazowiecki - Idzikowice at kilometre 18+600 (curve) and 21+300 (straight section). When measuring the acoustic signals with a microphone array (4x2), 8 meas-urement microphones operating in the audible range were used. The microphones were placed at a distance of 5 m, 10 m, 20 m and 40 m from the track centre, at a height of 4 m (from the rail head) and at the rail head (approx. 0.8 m from the ground surface). In addition, an acoustic camera with 112 directional microphones was used to locate the main noise sources, which was located at a distance of approximately 20 m from the track centreline. The identification of the main noise sources for high speed railway vehicles, basig on actual acoustic measurements, made it possible to isolate the dominant noise sources, as well as to find out the amplitude-frequency characteristics in the range from 20 Hz to 20 kHz, divided into one third octave bands.