A SENSITIVE APPROACH TO IDENTIFY BLACK SPOTS IN URBAN TRANSPORT, WITH APPLICATION TO CITIES IN ALGERIA

Global population growth and rampant urbanization have led to the accelerated development of large cities, which are themselves rapidly affected by a sudden increase in transport demand, or even a disruption of the daily concerns of citizens and the economic growth of the country. Currently, management of urban transport is a major issue in terms of the quality of life for citizens and the economic, social and cultural competition between the different cities. In many parts of the country, cities are booming, which has caused a major disruption in traffic. In spite of investments and development on urban layout, planning and development of means of transport in many cities of the country are faced with problems of massive influx of users, traffic jams, congestion, traffic accidents, and air and noise pollution. However, it should be mentioned that the problems are not identical and each city has its own specificities. The proposed working methodology is based on the identification of the problems in the field reported in the various national media and newspapers, grouped into five groups mentioned in the working approach. These are the black spots recorded in some wilayas of the republic, especially the big cities (Algiers, Constantine, Setif ...). Knowledge of the magnitude of the factors present on the ground makes it possible to have an overview of the malfunctions, or even perform « mapping of the black spots» to better choose the best directions to take. Thus, this study aims to highlight some of the urban transport problems encountered in certain Algerian cities and to then suggest possible solutions, or even identify actions to be undertaken on a priority basis currently and in the future.


INTRODUCTION
Global population growth and rapid urbanization have led to a sped-up development of large cities, which have been rapidly impacted by a sudden increase in demand for transport, i.e., infrastructure and services whose provision has been lagging far behind. Transport management is now a major necessity for improvement of citizens' daily life and competition between different cities. Efficient transport is clearly a fundamental aspect of good quality of life of every citizen. In many parts of the country, cities are exploding, which has led to huge traffic disruptions, causing traffic problems, resulting in greater disruption to the daily life of the citizen and the community. As a result, and despite investments and development on urban layout and planning and development of means of transport, many cities in the country are facing problems of a massive influx of users, congestion, traffic accidents, and air and noise pollution. Therefore, a unified approach to integrating multimodal traffic and an efficient supply network needs to be adopted, besides raising public awareness of self-disciplined behaviour. Thus, wellconducted urban planning has considerable implications for the growth of businesses and the profitability of citizens' daily lives. In this area, safety, comfort, availability, punctuality and quality of transport play a key role. However, it should be mentioned that the problems are not identical everywhere and each city has its own specificities, especially with the lifting of the state monopoly on public transport activity and it's opening up to private investment in 1988 while going through a phase of total, or even unrestricted, opening up of the urban passenger transport market [1].
Increased corruption in the sector has led to overlapping competences, prerogatives and disparities in the objectives to be achieved for the development of the sector [2]. Through this work, we attempt to highlight some urban transport problems encountered in certain Algerian cities, in an effort to come up with possible solutions. It is recommended to first identify all the factors having a negative impact on the urban transport climate and then to identify the actions to be undertaken on a priority basis.

METHODOLOGY OF WORK
We base the proposed working method on identifying and reporting urban transport problems in the various national media and newspapers. This type of observation is advantageous, as it does not influence the observed situation: it remains true to the reality of the phenomenon studied, which increases the reliability of the results. This provides a real picture of a situation. These are the black spots recorded in some wilayas of the republic, especially the big cities, grouped into five groups mentioned in the working approach, Fig. 1. The wilaya is a territorial public authority with legal authority and financial autonomy. It constitutes an administrative district of the state [3]. As a result, a qualitative approach based on a case study seems to be the most suitable for conducting this research, given the geographical nature of the Algerian context [4]. This work is based on the use of statistical data as an effective instrument in our case study to answer research questions pertaining to "what", "how" and "why" [5]. This qualitative research offers a global vision and a learning tool for local authorities. To act effectively, this technique must be part of a continuous improvement process: we measure, we act and then we observe the effects and the progress. It is a systematic approach to problem estimation that comprises measuring and categorizing the factors that have a negative impact on the urban transport scenario based on an informed judgement in terms of both consequences and relative importance [6]. It is a quantitative and graphical method that A sensitive approach to identify black spots in urban transport… 201 can help local authorities to prioritize and manage the dominant factors negatively affecting urban transport [7]. This technique allows us to take stock of each source of the problems (rolling stock, human factor, infrastructure, operations and environment). Thus, these conditions must be known and controlled by the authorities to offer citizens a high quality of traffic and mobility, or even to increase the positive atmosphere conducive to mobility [8]. Subsequently, knowledge of the factors prevalent in the field provides an overall view of the "black spots", which is crucial to better choose the best directions to take, as a localized problem could be quickly resolved. It is also useful to periodically monitor black spots to detect any changes throughout the network [1]. In addition, this overall view of the "black spots" makes further arguments about the need for action. It allows to have a presentation which makes easier identification of very concrete problems, rooted in the specific characteristics of the development in the field and in the experience gained. A portrayal of black spots enables better identification of the priorities that need to be focused on in solving the actual problems that have a negative impact on urban transport [9].

ISSUES RAISED
Our work is based on an inventory of the problems in the field reported in the various media and national newspapers (La liberté, El-watan, La tribune, journal open edition, Algeria-watch, Reflexion dz, Le matin, Le temps, Alg-focus). These are the black spots recorded in some wilayas of the republic, particularly in the big cities. In Table 1, we present the problems identified.

Wilaya of Constantine
Infrastructure Lack of regulatory stations. Lack of road signs at intersections. [10] Operations Lack of control of private transport in the field. Lack of traffic plans for new urban centres.

Human Factor
Proliferation of illegal transport.

Environmental factors
Rolling Stock A city with 50,000 taxis, of which 2,800 operate in the city centre.

Infrastructure
Lack of traffic lights. Urban maritime transport capacity is low. Bus and taxi ranks have mostly disappeared due to the low fuel prices of cars, which are far too numerous for the capacity of the roads.
[ [11][12][13][14][15][16][17] Operations Bus service is very slow, irregular and overcrowded. Lack of coordination between transport networks. Urban travel plan that does not take into account the needs of citizens. Energy and space consumption.
Public transport is almost non-existent in some regions. Rolling Stock Public transport system is no longer able to provide a satisfactory level of service for travellers. Deterioration in the condition of buses. Non-conformity of the type of vehicle operated with the standards. Poor safety conditions. Buses do not offer the desired comfort and security.

Wilaya of Oran
Infrastructure Road network is faulty and saturated, and the main roads are almost impassable.
Parking and security issues.
[ [18][19][20] Operations Long queues at bus stops during rushhours. Insufficient buses. Many Oranese communes remain inaccessible. Deficit in the number of buses, combined with a poorly organized rotation system.

Human Factor
Quality of service that is very often unacceptable.
Illegal taxis impose their diktat in these situations.

Environmental Factors Rolling Stock
Poor condition of buses.

Wilaya of Setif
Infrastructure Transport plan of the wilaya is not on the agenda. [21]

Operations Human Factor
Aggressiveness of personal's transport. Environmental factors Rolling Stock Used buses.  After analysing these identified black spots, we have grouped them into five categories of problems mentioned in the work process, Table 2.

Analysis
Urban transport management requires continuous improvement; we must therefore prioritize the actions to be undertaken in our action plans for effective management. Therefore, a prioritization strategy is needed that will give stakeholders a level of confidence and provide the requisite information; one such technique is the Moscow prioritization method [30]. It is widely used as a simple approach to prioritize requirements in an iterative context. Therefore, we have used the (20/80%) theory [30,31] and the Moscow method to prioritize and rank the most affected points for effective management without neglecting the daily preventive and corrective actions. With the help of this tool, we can build up the knowledge needed to control certain black spots in urban transport, and even to draw up a map of the black spots to prioritize the actions to be taken immediately; this is shown in Figure 1. From now on, this approach offers a global vision and a learning tool for local authorities. It enables the creation of a list of dysfunctions and to prioritize the actions to be taken in the various urban transport action plans based on the reality in the field. It represents a source of progress and continuous improvement in urban transport [32,33].
The problems were grouped into categories, and priority actions were identified on a 20/80 basis. The results are shown in Figs. 2 and 3. The analysis shows that the black spots and problem areas that need to be addressed first are operational infrastructure and human factor issues. Efforts should be focused on these areas without neglecting the daily preventive and corrective actions for the other problems. The resolution of these prioritized problems can positively influence the resolution of the other problems. As urban transport actions are a source of progress and continuous improvement, we propose an approach inspired by Pareto's escalator that meets these requirements, Fig. 4.
This approach proposes to climb the steps of efficiency by saving efforts on actions of lesser value [34]. The principle is simple: lighten the bottom of each step to allow it to rise. It is an iterative process that consists in renounce actions on the problems of a category, by reducing the time dedicated to others, to focalize efforts in the aim category. For our case, we distinguish 3 categories of action, namely [35]: • Essential Actions: actions of prime interest and urgency. This focuses on the top-priority issues identified by the Pareto analysis and the Moscow method. These are the actions related to operational/infrastructure/human factor problems.
• Important action: actions that are of high interest, but that can be implemented because of the actions identified as essential. These are the actions on rolling stock problems. • Desirable action: actions that are of definite interest, but that can be carried out if implementation possibilities arise. These are problems related to the environment.

Recommendations
Based on these results, the predominant factors that emerged from the Moscow prioritization techniques and the Pareto chart that require essential actions are operational factors/infrastructure factors/human factors; we recommend the following actions.

For operational problems
In this category of problems, the recent introduction of the tramway in enormous cities has resulted in narrowing of the traffic lane and a significant number of buses are not allowed to serve part of the cities internally.
In addition, a significant proportion of citizens do not own a car and do not live along the tramway's route. As a result, the population faces significant social and economic difficulties, as the transport system depends mainly on the availability of private cars and buses that serve tram stops with use of the same ticket. Therefore, with this change imposed by this new mode of transport, we suggest new organization of the traffic plan, while allocating a sufficient number and affordable rotation of buses to the most important tramway stations. The establishment of departure times is also important to ensure the reliability and efficiency of the network [36].
This step involves deciding the number of departures on each line and the time of each departure. The set timetable should best meet the needs of the users of the tramway network. In this way, we can make public transport more attractive by improving the quality of services and organization and thus encourage a significant number of citizens to use it more regularly.

For infrastructure problems
Urban parking problems are the most argued problems in this category. It is a structuring element in the functioning of the city and by its spatial influence; it represents a component of the urban landscape [37].
By exerting a "gate effect", it strongly determines accessibility to the different urban functions and by exerting a "leverage effect", it influences the modal choice of users' movements and the distribution of traffic flows.
Parking is a major factor for a more sustainable development of the city. Thus, an efficient parking policy represents a long-term strategy [38]. However, this is not the case in our cities, where we find the availability of parking spaces with a remarkable disorder of parked vehicles, Figure 5. We have adopted two solutions: off-road and on-road parking.

On-street parking
We propose a parking system with differentiated zoning and the following zones [38]: -short-term zone from 8am to 7pm, without residents, duration from 1h to 1h30; -medium-duration zone from 9h to 12 and 14h to 19h, duration 2h to 3h; and long-duration zone from 9h to 12 and 14h to 19h, plus 5h.
Fee-based parking will bring about order in the current chaotic parking in city centres [39]: -It will allow a faster turnaround and the sharing of public space between motorists wishing to park.
-It will improve traffic conditions and access to city centres, in particular, by reducing the amount of vehicles searching for free space. -It will allow better monitoring of the areas subject to taxable areas and will facilitate control; -The self-financing of the system is a strong argument for applying pricing.
-Paid parking will fight against the invasion of the anarchic parking lot on certain empty public spaces and will help to preserve it.

Off-road parking
For this component, we recommend a multi-offer parking system that meets the variety of use demand.
A classic offer is as follows: -Reception of vehicles subscribed with a guaranteed place, not provided by the road system [38]; -Payment at the right price (for the time duration of parking); -Unlimited parking time; -Communication with the user (video, intercom); -Adapted pricing (commercial, social ...); and -Security (social control, remote surveillance).
Intelligent parking offer (reservation). It is a car parking system based on allocation decisions and parking spaces allocated and reserved for drivers [40]. However, this system requires a platform that connects the different car parks with an information system. In addition, users have to download a certain application [41] that works with GPS and the location service.

For human factor problems
The problem of illegal transport is the most common in this category. They are an integral part of the transport supply; their share of the clientele is significant because of the lack of other legal modes of transport that do not meet the demand and the total absence of the latter on some routes [42]. Despite their usually stated disadvantages, the offers of illegal transport solve the problems [43]. In view of the flagrant lack of regularized taxi services, a system inspired by "illegal transport" [44] is necessary to organize and control them and to preserve their supply and guarantee flexible mobility for citizens.
-Its peculiarity is that the vehicles do not rotate constantly; they will systematically wait for customers at the stops before driving; -This is a transportation service typically dependent on customer needs; -When the vehicles arrive at a stop, they will try to pick up as many customers as possible and will only start their trip if the occupancy rate is above a certain threshold; and -In this model, the vehicles will never serve a destination that is not requested by a customer.

CONCLUSIONS
The analysis shows that urban transport management represents, obviously, a fundamental aspect of the quality of life of everyone and a major issue for the quality of life for citizens and the competition between the different cities. In addition, the study highlighted the black spots and priority problem areas that need to be addressed, which are issues related to operations, infrastructure and the human factor. This is where the efforts of the authorities must be focused without neglecting the daily preventive and corrective actions for the other problems.
Here, the role of the press in the development of the nation's economy must be welcomed. This enables promotion of safe and sustainable development in urban transport.
In addition, this technique is part of a continuous improvement process: we measure, we act and then we observe the effects and the progress. Therefore, we drew a map of black spots highlighting some urban transport problems in some Algerian wilayas; this study makes it possible to identify the actions to be undertaken on a priority basis immediately and in the future. Thus, this work allows decisionmakers to rank issues and black spots according to their gravity and importance from the field and identified by the various media. The European Commission has drawn up an action plan in line with the actions to be taken on a priority basis and thus to engage in a continuous improvement process based on the reality of the field and feedback based on experience. It must remain a source of progress and continuous improvement in urban transport. We can generalize this approach for all wilayas in the country.