| The thesis is devoted to the solution of the scientific and applied problem of the efficiency improvement of transfer nodes functioning due to the organization of the technological process on the basis of the account of the socio-economic parameters of interaction considering the stochastic nature of the duration of the technological operations.The scientifically grounded approach to the efficiency improvement of the transfer nodes functioning through the coordination of the interaction of urban passenger transport(UPT)from a perspective of ensuring the rational socio-economic and environmentally safe parameters of the technological process implementation are presented.On the basis of the proposed criterion,which,unlike existing ones,takes into account the environmental and social constraints,it was obtained the regularities of the influence of the schedule synchronization parameters and the dwell time of UPT vehicles at stopping points on the efficiency of the transfer nodes functioning.It was improved an approach to the schedule harmonization of UPT based on the coordination of the vehicle's arrival at transfer nodes,which takes into account the random character of the vehicles dwell time at stopping points at transfer nodes.The approach to synchronizing the timetables of vehicles at transfer nodes,based on searching the rational values of the departure time of vehicles from the initial stopping point was further developed.The thesis analyzes the urgent problems of the transfer nodes functioning and determines the ways to increase their efficiency.Among the main areas of research in the field of increasing the efficiency of the transfer nodes functioning,it is proposed the following:improving transport and planning solutions,studying passenger and pedestrian flows,as well as developing multimodal and intermodal passenger transportation,an organization of passenger transport interaction.The thesis shows that improving the efficiency of transfer nodes is possible by agreeing their functioning with the basic principles of sustainable urban development,that is,a comprehensive solution of economic,social and environmental problems.The transfer nodes development is ensured through the organization of a coherent operation of passenger transport,the priority issue is the synchronization of schedules.To achieve this goal,the following tasks are solved:-analyze the current state and substantiate the directions of increasing the efficiency of transfer nodes functioning;-to identify indicators for assessing the effectiveness of transfer nodes from the standpoint of alignment with the principles of sustainable development and formalize the performance criterion;-to develop a simulation model of urban transfer nodes functioning and to implement its software implementation;-to determine the laws of distribution of random values of the duration of technological operations and the parameters of the operation of transfer nodes;-carry out experimental studies to determine the influence of urban passenger transport interaction timelines on transfer nodes performance;-to develop a methodology for harmonizing the parameters of urban passenger transport interaction in transfer nodes;-assess the economic impact of the proposed transfer nodes efficiency measures.To develop the theoretical foundations of the functioning of transfer nodes used analysis methods to formalize the object of study used a systematic approach and methods of mathematical modeling.We used simulation modeling methods to develop the object model.Mathematical statistics theory was used to substantiate the laws of distribution of urban passenger transport time at transfer nodes and duration of traffic.Regression analysis methods were used to determine the relationship between the temporal parameters of the urban passenger transport interaction in transfer nodes and the criterion for the efficiency of transfer nodes functioning.The literature review suggests that the creation of synchronized schedules in passenger transport systems is a complex and important task,as well as a promising direction for improving the transfer nodes efficiency.The synchronization methods presented in the publications need to be improved: take into account the stochasticity of vehicles travel time and consideration of other parameters as random variables in models to reflect the real transport process.In addition,it is necessary to formulate an algorithm for finding a rational solution;the development of software for its implementation will increase the speed and accuracy of calculations.Among the identified areas for improving the efficiency of transfer nodes,the priority is to improve the technological form of passenger transport interaction.This issue needs to be investigated separately,as the possible benefits of transportation through transfer nodes are easily destroyed without a proper level of coordination of schedules.Synchronize schedules can bring quality public services to a new level by reducing the waiting time in the transfer nodes,reducing the burden on the transport network and the negative impact on the environment.Improving the efficiency of transfer operations involves two aspects.The first is to reduce the waiting time for passengers during the transfer to transfer nodes,the second aspect is to coordinate the arrival of urban passenger transport vehicles at stopping points to avoid their congestion.The synchronization of urban passenger transport schedules aims to reduce the transfer time between routes by simultaneously finding vehicles at transfer points.An important step in the study of any technological object is to determine the purpose and criteria of efficiency.The choice of the criterion of efficiency is one of the main problems in modeling,as it determines the composition and structure of the model and may differ depending on the specific scientific problem to be solved.In addition,the difficulty of choosing the criterion of efficiency is that the interests of the subjects of the passenger transport market(municipality,transport companies and passengers)do not coincide and are often antagonistic.The procedures for selecting performance criteria should take into account the needs of passenger market participants.There are certain emphases in the assessment of efficiency,which are shifted when there are transformations in society.The most commonly used are cost indicators.With the transition to market relations,the main goal of the organizers of the transportation process was not only to maximize profits,but also to provide high quality services and ensure the competitiveness of enterprises,so the criterion of efficiency also includes social indicators.Given the current environmental crisis and the direction of development adopted by most countries around the world,the efficiency criteria for any facility or system must also take into account the environmental component.The proposed three-dimensional framework of indicators for the assessment of the transfer nodes functioning covers economic,social and environmental dimensions aspects,and meets the modern requirements for a comprehensive assessment of the efficiency.The problem of multicriteria optimization,in which each indicator is considered as a separate target function,is formulated.For the possibility of evaluating alternatives and choosing values of the vector of input parameters,a criterion is presented that combines the monetary valuation of time costs of passengers and UPT.The components of the criterion include indicators to describe the technological process: transfer waiting time of passengers and dwell time of UPT vehicles at transfer nodes,as well as variables that allow the transformation of time costs into monetary equivalent.If the parameters of a stopping point are determined and justified,then it is necessary to solve the set of combinatorial optimization problems for coordination of schedules,the number of which corresponds to the number of loading areas at the stopping point.In order to ensure the environmental friendliness of the decision,the restriction is set: the waiting time of vehicles in the queue,when implementing the proposed solution should not be higher than in the base version.In addition,the criterion provides the introduction of a restriction on the number of conflict situations between the vehicles at stopping points at their simultaneous arrival.Indicators for the economic component are selected operating costs when finding urban passenger transport vehicles in transfer nodes.This is a function of the time made up of the duration of vehicle downtime in front of a stopping point waiting for the post to be vacated and the time spent at the stop.One of the main indicators of the quality of service for passengers is the time spent on the trip.Of all its components,the waiting time is the most significant for passengers[164–166].That is why this indicator is chosen as a component that allows you to display the social dimension of the functioning of transfers.The indicator of the environmental component,which takes into account the use of land resources to expand the stop,if necessary,and is a function of the number of posts of simultaneous finding of vehicles,forms alternative options for deciding on the values of transfer parameters.The measures have been defined that ensure minimization of unproductive downtime of vehicles and waiting times for passengers: determination of the number of loading areas at stopping points and the motion coordination of UPT vehicles.To develop realistic and adequate models,it is necessary to take into account the stochastic values of public transport performance,which occurs due to changes in traffic intensity during the day,congestion,weather conditions,driver behavior,etc.In addition,any changes in demand can lead to deviations in the time spent at bus stops.These uncertainties lead to an increase in the range of changes in the duration of individual technological operations and indicators of transfer nodes.Since the selected indicators depend on random variables,then each of them is a random variable,so it is necessary to move on to the problem of optimizing(minimizing)their mathematical expectation.The problem is solved in three stages.The first stage is the detection of the vector of input parameters,in which the selected efficiency criterion will reach its minimum,for which technological measures are applied.Because the task of synchronizing the schedules of vehicles arriving at the transfer nodes is NP-difficult,therefore,to find the vector of input values in order to optimize the objective function,it is necessary to use approximate algorithms that will provide intelligent search.The calculation is performed for each value of the number of posts of simultaneous finding of urban passenger transport vehicles at the stopping point under investigation.For other stopping points,the number is defined as a constant characteristic.Changing the number of posts is a technical solution,and is considered as a characteristic of the stopping point for the coordination of schedules under other conditions.In the second stage,a table of alternatives is formed in accordance with the number of simultaneous vehicles at the stop,where the decision-maker in the third stage determines the final parameters of the transfer,which will ensure their effectiveness from the standpoint of sustainable development.The developed mathematical model of transfer nodes takes into account the stochastic nature of technological processes and covers public transport,passengers,and a set of stopping points.Transport engineers often use approaches based on analytical models when making decisions about the development of public transport systems.The adequacy of such models is much lower compared to simulation,which allows researchers to consider stochastic parameters of technological processes.In addition,the internal connections between the elements of the system and the input parameters can be described with high accuracy,which makes the simulation models of public transport systems and their elements much more suitable for research.The operation of transfer nodes is a stochastic technological process,as its individual components are affected by a large number of environmental factors.This fact is taken into account in the model through the consideration as random variables of the duration of individual technological operations.To carry out experimental studies,the numerical characteristics required for the simulation model are determined.Transfer nodes as an object of infrastructure is a set of stopping points,for which the basic parameter is the number of posts for the simultaneous location of urban passenger transport vehicles.The matrix of the duration of the transition between the central points is also determined by the quality of the deterministic data indicating the functioning of the transfers according to the assumptions accepted in the model.Numerical values in these matrices are set based on the distance between the central points and the average speed of the passenger.As the main parameters describing the urban passenger transport,the selected moments of departure of vehicles from the initial stopping point,the duration of the movement to the transfer nodes,the time spent at the stopping point.To characterize the transfer subject "passengers",a transfer matrix is set,which reflects the value of the number of passengers who change between each pair of vehicles of certain routes.The model uses random values of the duration of movement to the transfer nodes and the time spent at the stopping point.That is why when studying these technological parameters,it is first necessary to determine the laws of distribution and their characteristics.To obtain the required numerical values of these data,field surveys were conducted on the route network of urban passenger transport in Kharkiv.On the basis of observations on the route network of UPT and at transfer nodes it was determined the parameters of the input data and the distribution laws of random variables of the vehicles travel time from the initial stopping points to the transfer node and the dwell time.The calculated values of the Pearson criterion do not exceed the table values,so the hypotheses are not rejected.The determined distribution laws and their parameters: the normal distribution for the travel time from the initial stopping point and the gamma distribution for the dwell time can be used in the simulation model.The implementation of the model at the level of individual transfer node is carried out using the Python programming language.It was developed basic classes: the Bus Line class is used to simulate the motion of UPT vehicles and technological operations performed at transfer nodes;the Transfer Node class is the base class,on the basis of which the implementation of the simulation model of the transfer node operation;the All Combinations class is a class that allows to synchronize schedules of UPT vehicles at transfer nodes using the brute force method or evolutionary algorithm and implement experimental studies in accordance with the developed experiment plan.The task of coordinating the schedules belongs to the class of combinatorial optimization tasks and is NP-complex.To solve such problems,an evolutionary algorithm has been developed that combines the modification of the genetic algorithm and simulation modelling,providing an intelligent search for the vector of input factors for large-dimensional problems.The algorithm that does not manipulate the values presented in the binary code,in contrast to the classical genetic one.Rules of the implementation of genetic operations are also different.To determine the influence of input data on the output parameter,which is the criterion of efficiency,an imitation experiment was conducted.As a response function,the components of the criterion are investigated: waiting time for passengers and waiting time in the queue of vehicles.The experiments consider the parameters of random variables: the standard deviation of the travel time to the transfer node and the mathematical expectation of the dwell time at the stopping point,as well as headways on the routes.The assumption is made that the following factors influence the total passengers transfer waiting time during the simulation period: headways of the UPT routes,between which the transfer is carried out,the standard deviation of their travel time and the mathematical expectation of the dwell time.Also,hypotheses of the functional dependencies of waiting time in the queue of UPT vehicles from the total dwell time at the stopping point during the simulation period are checked.Determination of the influence of factors both on the waiting time of passengers and on the waiting time of vehicles in the queue is conducted for the agreed schedules,that is,synchronization is carried out each time when the input data is changed.The obtained statistical data set as a result of experimental studies was processed with regression analysis,which was carried out using the function of the MS Excel analysis package.Automation of the experimental plan is implemented using the developed software,as a result of the calculations set values for the following indicators for each series during the simulation:-waiting time for urban passenger transport vehicles in the queue;-number of urban passenger transport vehicles in the queue(average number of possible conflict situations between vehicles at the stopping point);-total time spent by vehicles at stopping points in transfer nodes;-waiting time for passengers;-valuation of passenger time and urban passenger transport in transfer.As a result of experimental research,an array of statistical data was obtained.Analyzing it,it is assumed to establish an approximate analytical functional relationship between the input factors and the response function,which allows regression analysis.To do this,it is necessary to form alternative hypotheses about the form of regression models.Then you need to determine the coefficients of regression models and choose the most appropriate.The components of the criterion are considered as a response function:waiting time of passengers and waiting time in the queue of vehicles.Hypotheses about functional dependences of waiting time in the queue of urban passenger transport on the total time of vehicles at the stopping point for the simulation period are formed.The value of the difference of the mathematical expectation of the moments of arrival of vehicles in the transfer nodes is experimentally established,which will provide the minimum value of the waiting time depending on the parameters of the movement of vehicles and the time of their stay at the stopping point.The obtained regression model to determine the time spent by passengers during the transfer will formalize the influence of the time spent by vehicles at the stopping point in the transfer nodes on the criterion of efficiency in synchronized schedules.Note that this statement is true for transfer nodes,in which the organization of vehicle traffic and design parameters of stopping points ensures the absence of unproductive downtime.The rational time of vehicles at the stopping point in the transfer nodes corresponds to the value at which the criterion reaches its extreme(minimum).Models for waiting time in queue for one and two loading areas at the stopping point and the waiting time for passengers are obtained.Using the model to determine the passenger waiting time,it is possible to estimate the value of the criterion for the synchronized timetable,taking into account the constraints.The proposed criterion of efficiency and the formed contour of the formation of management decisions allow determining the parameters of the operation of transfer nodes for tasks of different types and complexity.According to the proposed technique the best alternative is chosen by analyzing the resulting estimated values of the criterion for each number of loading areas,taking into account social and environmental constraints.If the problem statement includes argumentation of the dwell time at the stopping point at the transfer node for a particular route,the table of alternatives expands-subalternatives are added.The brute-force method and the evolutionary algorithm,as well as calculations in accordance with the established analytical dependencies,allow the estimation of the criterion value for the agreed schedules.Thus,it is possible to solve problems in comprehensively or separately for directions,taking into account the conditions and specifics of the problems of the transfer node functioning.Testing results of research are carried out in Kharkiv city,Ukraine: it was considered a transfer node in which there is a combination of ground passenger transport routes.As a result of the calculations,it was determined that for the transfer node,which is located at the intersection of the streets Heroi'v Pratsi-Hvardijciv Shyronintsiv,it was determined that the effect can be achieved with the existing number of loading areas due to synchronization of schedules and increased dwell time for a dedicated route up to two minutes.The practical significance of the obtained results is a methodology for the schedules synchronization of public passenger transport at transfer nodes and the motion optimization of vehicles on the elements of the city's transport network.The results of the thesis are used in the educational process of the Kharkiv National Automobile and Highway University. |
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