Analysis of the offer and demand for the transportation of people from a settlement in the city of Skopje

Transportation planning is a complex task and a major challenge that plays primary role in the development of the economic processes in the exchange of people and goods. There are several approaches from which transport can be analysed. As an economic activity transport is analysed in terms of offer and demand. The offer of transport is an offer of given capacity which can transported from one place to another. The offer analysis is made in relation to the demand for transport which is made by the individuals that travel or the firms and industrial facilities that want to transport goods. An initial representation of the theoretical approach in the analysis of the transport of people through the description of a specific case is shown in this paper.


Introduction
In order to enable the progress of transport, large financial funds are needed which should be invested for its functioning, that is for the construction of the infrastructure, for the production and procurement of vehicles and for the organization and exploitation of the transport.These investments are based on the analysis of the functioning of the transport service markets, by studying: the characteristics of the demand, the characteristics of the offer and the transport service market (equilibrium, etc.)

Target group
In the analysis the target group whose mobility was studied was a group of students studying at several faculties in the city of Skopje.Common for all the students is the place of residence, i.e. the settlement Dame Gruev located in the municipality of Gjorce Petrov.From this group all the relevant information about their mobility was obtained through a survey process.

Environment characteristics
The settlement Dame Gruev is located in the west part of the city of Skopje approximately 7 km from the central area.It extends at 2,5 square kilometres with a modern urban plan and has around 15000 inhabitants.Nearby there is a military barrack and part of the railway that goes towards the cities of Kicevo and Prishtina.
Currently the only way to travel to other city areas is via the road network (city streets), because the existing railway is not used for urban transport and there are no other transportation alternatives.However the approach ("entrance" and "exit") of the settlement Dame Gruev is limited to one street that is through an overpass at the very beginning.The other way that does not represent a suitable approach to the settlement is through the city ring road.

Methods
This article contains analyses and descriptions of the transportation offer and demand which affect the target group and the city in general.

Analysis of the transportation systems
Considering the transport vehicles, the alternative to the individual transport (cars) is the public city transport that is represented by the buses of the public city enterprise Skopje.On the territory of the settlement pass 3 different lines of the public city transport, the buses 22, 22A and 64A.Two of them (22 and 22A) represent city lines, and the other one is a suburban line.
The line 22 has a length of 14,5 km with 30 stations from which 3 of them are in the settlement Dame Gruev.This line passes throughout the most vital city areas.The travel time in one direction from the beginning to the end of the line is 1 hour, i.e. the duration of one rotation is 2 hours.The time of departure of two consecutive buses varies from 7 (in the morning) to 20 (in the evening) minutes.The line 22 is one of the most busy and most frequent lines in the city of Skopje.There are average of 110 rotations per day.
The other two lines (22A and 64A) have similar characteristics (length, stations, travel time) as the line 22, but different ending points and drastically less rotations per day.
Generally on the lines throughout the city the transporting is done by two-deck buses.This buses by the brand "Yutong" have length of 11,8 m, height of 3,9 m and capacity of 80 passengers (60 seating and 20 standing).In addition to these, there are also single-deck buses from different brands with a capacity of 50 passengers with various seating and standing combinations.In average, the commercial speed of the buses on the city lines is around 14 km/h, but it should be taken in consideration that the legal speed limit in the cities in Macedonia is 50 km/h.The accuracy of the timetable of the busses is 5 to 10 minutes give or take, and it depends on several factors.Also it should be emphasized that the frequency of the buses varies throughout the week, i.e. there is difference in the timetable on weekdays and weekends and holidays.Fig. 2. Two-deck city bus from the brand "Yutong"

Analysis of the demand for transport
Through the analysis of the target group, valuable information about their mobility has been obtained.Such information's are: -Generation of trips -Destination of trips -Main and secondary motives for traveling -Distribution of trips by the means of transport -Time distribution of trips throughout the year, week and day.These information's are used for determination of the transportation demand.From spatial aspect the people who travel to destinations near the route of the line 22, don't have a problem with the public city transport.For the other users of public transport who travel to different city areas, where there is no direct line from the settlement or the rotation intensity is very low (line 22A and 64A), problems occur which lead to loss of time and money.
In terms of transport capacity there are major problems in the public city transport.The line 22 is one of the busiest and most packed lines in the city of Skopje, because it passes through the most frequent areas and settlements where it is the main transport offer.Due to this and the fact that the other lines (22A and 64A) have low frequency, the buses very often reach their maximum capacity.This mostly occurs in the morning hours (from 7 to 8 o'clock) and the afternoon hours (from 15 to 17 o'clock) when most residents have the need to travel.
Besides the capacity of the transport vehicles there are problems with the capacity of the streets.Because the infrastructure in the settlement Dame Gruev is reduced to one main street with two traffic lanes, the maximum traffic density is often reached.This condition affects all users of the road and leads to breakdowns in vehicular flows, traffic accidents and overall low level of service.

Results
The current state based on the data from the analysis of the offer and demand indicates major transport problems in the settlement Dame Gruev and the city of Skopje in general.At the moment besides the individual and the public bus transport there is no alternative solution.Besides the improvement of the current transport offer, possible alternatives for the transport problems in the settlement Dame Gruev and the city of Skopje are: -Construction of new infrastructure i.e. streets that will improve the access to the settlement and reduce the traffic volume on the existing streets.Positive sides to this solution are: traffic distribution, improvement of the level of service, increased traffic safety, faster time of travel and more.Negative when building a new infrastructure in city areas are the major costs and the problems that arise when constructing in densely populated places.
-Implementation of a tram in the public city transport would generate great benefits for the users of the public and individual transport.With a tram solution there would be faster, more accurate and cheaper transportation for the users.This solution should be considered at the level of the whole city, and requires detailed analysis, planning and large investments for the infrastructure, vehicles and expropriation.
-Utilization of the existing railway in the public city transport can be done with an adequate reconstruction and integrating new lines.The existing lines pass through a few settlements in the city and most of them have little frequency of trains, which makes them suitable for this kind of transformation.

Conclusions
The analysis of the offer and demand for transport represent compulsory process when there is a requirement for solutions to a certain transportation problem.This could be oriented to the improvement of the existing state of the transport, as well as finding and implementing a new transport system.The analysis its self is a complex and long term process that involves several areas of expertise.For the particular case stated above the results of the analysis indicate a major transport problem from several aspects.The solutions for this problem are proposed through three alternatives.The future research based on this analysis should be pointed towards the design of a model, which will serve for the prediction and planning of the mobility in the future.With detailed analysis, careful planning and proper design the urban transport can function properly.Skipping or leaving out some of the phases usually lead to problems which are manifested as a loss of time and money.

Fig. 1 .
Fig. 1.Air distance between the settlement Dame Gruev and the city centre