Abstract
Contents
- Introduction
- 1. Theme urgency
- 2. Goal of the research
- 3. Review of existing approaches
- 4. Statement of the problem
- Findings
- References
Introduction
The transportation system in the most general case - is forming cohesive whole set of employees, vehicles and equipment, elements of the transport infrastructure and transport infrastructure entities, including the control system to ensure the efficient movement of goods and passengers.
An efficient transport system can not be regarded as part of achieving optimal performance of the processes involved in the system. The main objectives of the transport system are meeting the needs of the economy in the transportation of goods and the mobility of the population. Therefore, the efficiency of the transport system will always be determined by the kind of balance between the conflicting demands of the economy and society. A striking example is the desire of passengers to transport pulled up to a stop as soon as the passengers came up to it, and the desire to establish a carrier such headway that vehicles were always filled to capacity and yield the maximum profit. Thus, for an effective transport system knowledge in the field of transport combined with the economy, urban planning, geography, ecology, sociology and psychology needed.
In economics, the transport industry has a particular position, referring to the economic infrastructure. Transport is part of the productive forces of society and is an independent branch of material production, ensuring the normal operation of the economic system as a whole. This implies that the production of transport has a material nature and is expressed in the movement of the real product of other industries.
A specific feature of the transport system is the cyclical nature of their work. The starting point of the operating cycle of the transport system is to feed the empty rolling stock for transportation. Transportation of goods - this supply of rolling stock to be loaded on passenger transport - exit the bus with the destination of the route. Depending on the technology of transport operations and traffic management in the transport cycle can be performed various transport processes associated with the loading or unloading cargo, embarking or disembarking passengers. Transport cycle ends on arrival empty rolling stock for pickup or at the start of the route passenger bus.
In the real world to perform transport cycle affects a significant number of different disturbances and most of which are random, so the main features of the transport cycle, such as its duration is usually very unstable. In order to stabilize them must be taken to reduce the number of disturbances. This, for example, an organization dedicated lanes and priority traffic signal control for urban public transport.
The transportation system is a unique example of the collective behavior of its members. In connection with this collective behavior is a powerful factor in shaping patterns of functioning of the transport system. And the processes of self-organization leads to the formation of multiple layers of sustainability of the system, forming a hierarchical structure of collective adaptation to different temporal stability.
In this respect, we can distinguish the following three structural levels:
- seats by forming, processing and consumption of goods, the resettlement of the population;
- organization of transport processes in the network;
- shaping traffic on parts of the network.
Transport systems are at the forefront in providing almost all industries of the economy and society. Naturally, the efficiency of their operation is essential for the development and improvement of the economy and quality of life. Improving the efficiency of transport systems involves solution set of interrelated problems, which can be attributed to the problems of a higher level, as they go beyond the narrow transport problems. Governance of urban passenger transport (GUP) must be accompanied by tracking changes in all forming relationships that determine the activities of the system and its effectiveness. To do this, do not spend enough complex and which can have adverse effects on the experiments in real systems, the TGV, requires the use of models. In order to preserve the accuracy and informativeness of the model will be justified to identify and include in the model management system GUP its basic relationship with the environment, which includes relationships with consumers and the state. As the domestic and foreign practice, these relationships are the main constraints on the system performance GUP.
As the experience of the GUP system control to a systematic approach has been implemented in practice, it is useful to consider the various options (sections) modeling system GUP. One such option is considered in simulation of V. Feenman [1]. The author distinguishes engineering and economic models to solve the problem of how to improve the management of the GUP system.
Engineering models, public transport management covering space and technical characteristics of different types of public transport. It is proposed to create a coordinated hierarchical network services that combine the advantages of different types of public transport. This approach has practical application in the German-speaking area of Europe. Economic models are based on the fact that the organizations providing public transport services do not show flexibility, and pay little attention to the needs of passengers. Economists believe that the solution is to change the regulatory framework. Passenger transport enterprises should be responsible for the quality of services and bear the financial costs or receive appropriate profit. This approach is supported by the Anglo-Saxon part of Europe.
As none of these approaches alone can provide the level of mutual benefit transportation, arranging as enterprises providing public transport services and public transport. The state also has an interest in the efficiency of transport, as with the same number of passengers may get more money in the form of income taxes carriers. In addition, in many countries, including the CIS countries, the state itself provides public services, public transport, which certainly needs to improve its efficiency in order to save the budget.
As V. Feenman noted, "a theoretical model to show how the need to share legislation, coordination and design services for maximum efficiency" [1]. In other words, you need to find the best combination governance and regulation of GUP and the development of competition in the system. This should be regarded as the economic impact of agile methods, and measures for the direct determination of the parameters of the system through the establishment of timetables, schedules and driving modes, as well as coordination of the operational activities online.
The study identified a set of system requirements from the GUP of demand for transportation, which are estimated based on various public transport system. These requirements can be summarized as follows:
- urban passenger transport must ensure the integrity of the city as a geographical entity and the public demand for transportation must be forecast and manage;
- for political reasons fare GUT should provide accessibility for socially vulnerable segments of the population;
- operational performance to meet customer requirements;
- required budgetary subsidy to be real, stable and stand for certain results, taking into account the level of service quality.
1. Topic relevance
Now in the big cities there is a problem of public transport congestion in the so-called "peak hours." In these hours public transport loadness disproportionately increases, which leads to the fact that he can not cope with the number of passengers [2]. This means that people can not make it to work or get depressed because of the congestion. These factors have a negative impact on employee productivity and, as a consequence, the economic growth of the city.
2. Research goal
The aim is to optimize public transport, provide load on it for the day.
Research object: passenger transport system of the city.
Research subject: optimize costs and increase the benefits of carriers.
As part of the master's work is to get the actual scientific results for the following areas:
- Development of a model to describe the system of passenger transportation.
- Determination of the optimal parameters of the system under the given constraints.
- Develop recommendations for the implementation of the results in the production practice.
3. Review of existing approaches
Optimal planning of transportation systems, principally allows to overcome most of these challenges, based on a system of interrelated mathematical models, in which manages accounts such transport systems, as blurred the information available, the contradictions in the interests of partners, a multi-purpose nature of the evaluation selectable modes of operation, etc. based on these models, it is possible to formalize the optimization problem and use appropriate mathematical tools [3].
In A. Gorev's work [4] there are several classes of optimization of transport systems:
- Tasks transportation routing and vehicle movements are to the choice of rational or optimal patterns of movement of goods or passengers between a finite number of points.
- Problems loading vehicles determine the range, size and layout of the cargo during transportation.
- Scheduling Problems arise when serving process manufacturing companies (transportation of concrete), the transportation technology "just in time" when loading or unloading the vehicle in large warehouses and terminals, passenger transport.
- Planning tasks of labor and technical resources to solve transportation hub to optimize hub-common and specialized for each type of transport resources in order to reduce the downtime of all kinds of resources, increasing productivity hub.
- Task planning transportation facilities affect transportation (transportation planning) and operational (execution of maintenance, the use of frames) the activities of the enterprise.
- Objectives of production and transportation planning related to logistics, when the criterion of minimum total cost of production and delivery of the products is determined by the plan of production, distribution and storage of finished products in the presence of alternative sources of supply and consumption of interchangeable products.
- The problem of determining the optimal tariffs to maximize the revenue of the transport company by conducting some marketing policies.
Thus, we can see that the current approaches to transportation problems solving is not considered for the selection of the direction of optimization, as directed to other areas, such as optimization of transportation or building maps of possible locations congestion.
4. Statement of the problem
In order to improve public transport in this paper we consider the problem of finding the optimal number of taxis needed to transport all of the passengers on the routes they need with a view to minimizing costs and maximizing benefits carrier of passengers.
Solution to this problem will determine the appropriate fleet to provide transportation needs for the population of the city of the interests of carriers and consumers.
To solve the problem it would be advisable to conduct a large-scale study of the dynamics of traffic at him for a long time (about a month) for the detection of specific laws and recording them in the proposed model.
Problem in the general form can be put as follows. Need to build a model to determine the number of taxis needed to transport the passengers to the city they need routes with a view to minimizing costs and maximizing benefits carrier of passengers.
Also, be aware that some of the variables may be connected not only through the functional, but also directly with each other through some of the equations.
In this paper, we consider the special task: to build a model to calculate the required number of taxis to transport people on the same route with optimum transit times of all passengers, the carrier's profit and cost of travel.
Enter the following values:
Income carrier:
The time of carriage:
Then we can put the optimization problem as follows:
where t – time;
– number of passengers, which is necessary to transport;S – fare;
Z – spending of carrier for one taxi;
– travel time on the route; 
– number of taxis; 
– the maximum number of passengers in a minibus; 
– weighting factor. Also, it is advisable to solve the problem using the following restrictions:
- Carrier revenue exceed its spending;
- Fares for passengers should not exceed 5 UAH;
- The carriage time shall not exceed 16 hours.
Thus, the task is optimizing of the function 
. Since the minimized function is dependent on several variables, the method can be chosen for gradient descent method:
where
– optimization vector [5].
Since most of the features of this type of gully (ie, in a region of the gradient vector norm is substantially less than in the rest of the space), it makes sense to ensure the convergence of the algorithm to the solution, because this method has quite slow convergence.
To increase the convergence of the algorithm to the minimum of the function at 
can be used to find the optimal values of the conjugate gradient method:
where
– optimization vector [5], 
This method allows to find a solution with the required accuracy for a finite number of iterations.
Findings
In the course of this work we considered the problem of optimization of passenger transportation in the city. In order to improve public transport in this work we consider the problem of finding the optimal number of taxis needed to transport all of the passengers on the routes they need with a view to minimizing costs and maximizing benefits carrier of passengers.
Also analyzed the current approaches to modeling of transport systems and a review of the existing problems of the optimization of transport systems.
The formulation of the problem has been proposed to be addressed in the optimization of passenger transport in the city.
References
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