Chapter - I Introduction and Statement of the Problem

Transcription

1 Chapter - I Introduction and Statement of the Problem

2 Introduction The topic Topological Model for Traffic Management in Urban Centres A Data Base Management Systems approach has been chosen after some events encountered. The First one being, an accident suffered by a girl, who visited twin cities of Hyderabad for computer education anticipating a greener career. She was travelling by Public Transport., as she got down the bus was crossing the road only to be hit by a speeding car overtaking the bus she just got down. Shows the need for minimizing accidents. Second instance, a resident who wanted to catch a train at Railway station 5 k.m. away, was looking for an auto, to catch the train ready to leave in 10 minutes, enquired how-long it will take to reach the station. This question although looks simple, is difficult to answer. The auto-driver replied that the distance is something like 5 k.m., can be covered in 5-8 minutes. But there are 5 signals to pass, taking anything like 5 minutes at each signal, need additional 25 minutes; hence it takes 30 minutes at minimum. By that time the train will leave the station. This has prompted me to look for minimizing the waiting time at traffic signals. The Third, report in Newspapers, that Police Personnel supervising of traffic at intersection, are suffering health hazards due to vehicular pollution. I have also noticed that a large number of two wheeler users and their Pelion and some pedestrian too, tie a hand-kerchief, a scarf around 1

3 their face to protect themselves from vehicular pollution. Shows there is every need for minimizing vehicular pollution. It is well recognized that application of Data Based Management System would improve the efficiency and effectiveness of any System. Accordingly, I have opted the topic Topological Model for Traffic Management at Urban Centers a Data Base Management System approach. In view of recent reports that Engineering solutions of Education, Engineering and Empowerment have offering only temporary relief and not permanent solution to the problems, I have decided to adopt a Mathematical Modeling approach of Topological Graph Theory to simplify the Traffic Management. 2

4 The National Priority on Urban Mobility : Urban mobility faces several problems. Union Government has been trying to solve them, by Five Year Plans. World over the problems of Mobility has been tackled by speed mobility solutions and providing infrastructure like road widening, flyovers, pedestrian walkways, over - bridges and sub-ways. The Working group constituted by the Ministry of Urban Transport has evaluated the approaches and came to a conclusion that they are providing only temporary relief and thus the problem needs a fresh look. Hence it is felt that a Mathematical Modeling approach is worthy. My approach to the problem is as follows: To make the study simple, I have adopted the approach of Topological Graph Theory, which is distinct from other branches of mathematics. As a Mathematical Modeling Tool this approach has facilitated graphical representation of the problem and I am able to use the principles of planarity, connectedness, isomorphism, decomposition/ partition, to simplify the traffic management problem of accident. This has facilitated me in controlling the number of conflict points and to evolve simpler signaling system to save time of the commuters. The traffic signals need simplified approach to eliminated wastage of time and fuel at traffic signals and also to reduced exposure to vehicular pollution. 3

5 Objectives of the study : The objectives of the study are 1 To control Road Accidents (between vehicle-to-vehicle and Vehicle-to-Pedestrian) at Urban Centres.. 2. To Minimize, waiting time at Traffic signals (4-leg intersection and Pedestrian Crossing) resulting in time loss and Wastage of fuel. 3. To minimize the intensity and duration of exposure to vehicular pollution, suffered by the commuters at Traffic Signals The Tertiary Objectives are : a. To improve average speed of commuting. b. To improve overall capacity of the road. c. To improve fuel efficiency of the vehicles Scope of the study: 1. The study concentrates on Model for Traffic Management at 4- leg intersection and Pedestrian Crossing. The T-intersection (three and multiple legged intersections) are outside the scope of the study. 2. The approaches of speed transport modes (BRTS, MMTS, Metro, Light Rail) and their repercussions are outside the purview of this study. 3. More emphasis is attached to safety, saving of time and fuel and exposure to Pollution and hence improving efficiency of traffic management by using DBMS will not be covered. 4

6 Overview of Traffic Accidents in India during the year Majority of the road accidents Vehicle-Vehicle and Vehicle- Pedestrian are encountered at intersections. Pedestrian suffer accidents while crossing the road. To solve the problem several congestion. Road widened. This has resulted in commuting by multi-lane system facilitated overtaking, has resulted in increased accidents and congestion and other connected problems in urban mobility. Problem of overtaking from left and right; speeding up or slow down or stopping suddenly. Entering from by-lanes and driving into has been common; availability more capable engines without corresponding driving skills is also found to be a reason. Public transport buses do not have dedicated lanes. They overtake other commuters and commuters too have the option and have to bear with condition of the road. Buses have to stop every 500 mts in the name of commuter convenience. Pedestrian crossing the road wherever they please. They also take L-turn, U-turn at intersections, to follow their route. Wastage of fuel is rampant, emission by vehicles is common. Vehicular Accidents - overtaking, taking turn, changing lanes by two, three, four wheelers. Pedestrian suffer accidents while crossing the road, to catch bus or going to work place after leaving the bus. a. Congestion, accidents, vehicular pollution and unbearable costs of traffic management are universal phenomena. Working Group on Traffic Management of Govt. of India has gone in to the problem 5

7 and evolved approaches for urban mobility, has suggested establishment of Centers of Excellence, b. Experts in Traffic Management have opined that Roads Widening and Flyovers at enormous costs are not resulting in sizable improvement of the situation. c. The Working group on Traffic Management has also studied the approaches following worldwide and came to the conclusion that they are not fit for Indian situation and found to be a costly approach. Have suggested for fresh look to the problems to find an indigenous solution. The following table shows the number of road accidents (in thousands), Number of persons injured and persons killed during the years (India) ( 000) Sl.No. Year Road Accidents Persons injured Persons killed ,05, ,14, ,18, ,26, ,33, ,36, ,39,091 Source :Col.9 of Road Transport Year Book, Min of Road Transport & Highways, GOI. (Figures in Lakhs) 6

8 Road Accidents Road Accidents Persons killed Persons killed Most of the accidents at Urban Centres, between vehicle take place at intersections and pedestrian suffer accidents while crossing the road. Highest incidences of Traffic Accident cases was reported in Delhi City (7479) which resulted in 5809 injured and 2829 deaths; Bangaluru (6490) cases, 5376 injuries and 832 deaths; Mumbai 4008 cases, 3492 injuries and 785 deaths;. The number of Accidents, Injured and deaths occurred during the yea at 35 major centres are given in the following trable. 7

9 Accidents at 35 Mega Cities Accidents Road cases Injured deaths 1 Agra Ahmedabad Allahabad Amritsar Asansol Bengaluru Bhopal Chennai Coimbatore Delhi Dhanbad Faridabad Hyderabad Indore Jabalpur Jaipur Jamshedpur Kanpur Kochi Kolkata Lucknow Ludhiana Madhurai Meerut Mumbai Nagpur Nasik Patna Pune Rajkot Surat Vadodara Varanasi Vijayawada Vishakhapatnam Total

10 Approach to the problem : Urban Road are network of wide roads and intersections While accidents between Vehicles are encountered at intersections, pedestrian suffer accidents while crossing the road, these two spots are selected for the study. The traffic movement at the spots was studied and the reason for accidents is found to be encountering a large number conflict points (High Crossing Nnumber of the Graph). Accordingly, we have taken up minimize/ eliminate the conflict points using the methods of Mathematical Modeling of Topological Graph Theory. The Graphs of Intersection and Pedestrian crossing were prepared. The Number of Conflict points represented by edge crossing (Cross Number) were 16 and 4 respectively. In the second phase, the traffic signals were studied. It was found that the Traffic Signals at intersection operating in four phases, while that of Pedestrian Crossing in two Phases. Thereby each leg commuters are waiting for 3 phases of the signal at intersection, while Pedestrian signals are stopped for one phase. Thereby much time and fuel (while idling at signals) were lost. We need to simplify the waiting time. The intensity and duration of Vehicular Pollution at intersection and Pedestrian signals were worked out. 3 leg commuters contribute to pollution at intersection signals. Each commuter suffers vehicular pollution for a duration of 3 Phases of the signals. We need to simplify the duration and intensity of pollution. 9

11 Using the methods of Graph Theory, the Graphs of Intersection and Pedestrian Creossing were simplified to minimize the crossing number of their graphs and adopted to the traffic management at these spots, Which reduced the scope of accidents and improved the signals. The solutions were recommended of adoption. achieved. And I am happy to report that all the objectives of the study are Simplification of Traffic Management and Operation of Traffic Signals at Intersection : The problem of large waiting time at busy signaled intersection will be studied and the number of phases in which signal operated is noted. The numbers of conflict points encountered at the intersection will be recorded. Using the methods of Mathematical Modeling The 4-leg intersection and pedestrian crossing are represented by Graph in the form of Vertices and Edges, and make them Planarity (by eliminating edge crossings). Using the methods of Graph Theory, the edges are altered and intersection graph is partitioned into non-empty planar sub-graphs. The non-planar part of the graph will be represented as union of isomorphic sub-graphs. The traffic on these edges ply without hindrance (accident). The remaining portion is proved to be of thickness of ONE. Since it cannot be Planar, we have opted to introduce come controls by Traffic Signals and revise the Graph to 8 Conflict points and adopted it to intersection with Traffic Signals operating in two Phases, to save fuel and time. 10

12 Simplification of Pedestrian Crossing and its signals: The problem of large waiting time at busy signaled pedestrian crossing will be studied and the number of phases in which it operates, is noted. The number of conflict points encountered will be recorded. Using a Mathematical Model, the graph of Pedestrian Crossing has been simplified. Finally, modified Graph is adopted to traffic management at pedestrian crossing. This would minimize the waiting time of commuters. Observations on approaches to traffic management: a. Road Widening: When roads widened to 100 and more, they have facilitated use of the road in 4 lanes outward and another 4 inward. Are permitted to overtake from left and right freely. Vehicles change lanes using speed, apply breaks when necessary, they overtake from left or right of a vehicle. When traffic jam occurs, they drive at snail pace, as also follow the car rule is not mandatory, they overtake, stop or speedup at will. Hence, may be hit from behind, or may hit vehicle in front of them, side swap may occur. Such happenings increased after road widening. b. Road widening has increased the road width. Thereby, pedestrian are required to walk large distance to reach the other end of the road, thereby take longer time to cross the road. Vehicle drivers complain of increase in their of waiting-time at pedestrian crossing. c. When 3-4 lane vehicles reach the intersection, each one option to take left leg, opposite leg, right leg by commuters of all 4 legs, the 11

13 number of conflict points increase in multiple. Thereby more congestion is encountered. d. No exclusive bus lanes are provided, hence overtaking by bus and overtaking bus by vehicles freely happen. Bus stops at bus stops, and vehicles following them or overtake often hitting the pedestrian who get down from the bus. e. The bus has two entry/exit doors, one at front and other at the back. When bus stops, commuters alight the bus from these doors, cross the road from the front and back of the bus, being hit by vehicles overtaking the bus or vehicles driving from opposite direction of the bus. When the bus stops at the bus-stop, the vehicles behind the bus will overtake the bus, may hit the pedestrian crossing the road. The accidents have increased as a result. f. During the waiting time at the signals, the engine of the vehicles are not switched off. The vehicular exhaust causes pollution and commuters waiting at signals are exposed to. At a 4 leg intersection, traffic signals operating in 4 phases, always 3 leg commuters will be waiting at any point of time. Again, each commuter waits for 3 phases of the traffic signal to get their turn to cross the intersection. g. To prevent pedestrian crossing the road, road dividers are created from one intersection to another. Except at pedestrian crossing. The vehicles who need to take U-turn are prevented and forced to take U- turn only at pedestrian crossing or next intersection, causing congestion, as U-turn requires more space and time. Further, 12

14 incidence of wrong side driving is observed putting commuters prone to accidents, often fatal. h. Increase use of Public Transport results in increase in number of pedestrian crossing the road: It is observed that each person using public transport is required to cross the road once at commencement or work place, either in onward journey or return, that is twice in a trip. Hence, sufficient capacity of pedestrian crossing are to be created, since twice the people using public transport user would cross the road. i. The driver/pedestrian requires 3 seconds time to take corrective action, to avoid accident. The time is provided. j. Vehicular exhaust is attributed to 70% of pollution in cities. Pollution is due to driving at subnormal speed; stop-start operations and not maintaining vehicles properly the pollution is high at traffic signals. At any time commuters of 3 legs will be waiting at intersection. Each leg commuter will wait for 3 Phases of the signals. Hence, 75% of the vehicles that cross the intersection contribute to pollution at intersection, through out the day. k. Capacity of intersection is the number of vehicles use the interchanges. Need to be improved. l. It is found that introduction of Road dividers to restrict Pedestrian crossing the road (to save from accidents) has caused inconvenience to Vehicular commuters. The dividers force vehicular commuters to take U-turn at nearest junction, increase in jams, severing congestion and accidents to vehicular commuters. Installing dividers without 13

15 provision for road-over bridges or sub-ways for use of pedestrian is not a good approach. m. After roads are widened, vehicles ply in 3-4 lanes in each direction and Road dividers are constructed. There are no road over bridge or underway. Pedestrian are at mercy of vehicular drivers (to cross the road). Instances are common that Pedestrian look for auto to cross the road. n. The Signaled intersections donot provide for U-turn, thereby congestion and accidents are resulted. o. The motor cyclists donot have the concept of breaking time, breaking distance, purpose of horn. Thereby, change lanes, stop or speed up. p. The motorcyclists are not aware that it requires 3 seconds to notice a danger and to take corrective action, thereby fall pray to accidents. q. To Main Roads and Streets are not separated, thereby slow and speed moving vehicles ply on some roads, there by congestion, accidents are common. r. In case of encouraging use of public transport in place of self-driven vehicles, it is found that the need for road crossing by pedestrian has increased in proportion to the number of people using public transport. Each commuter taking public transport is required to cross the road two times in a trip. Without corresponding facilities for crossing the road (road-over bridges; sub-ways), the recommendation results in increase in pedestrian suffering injury or fatality. Hence the recommendation to use public transport to 14

16 individual driven vehicles needs a fresh thinking in view of observation. s. Since, the Engineering solutions of widening of roads, building flyovers of different kind involve high investment and the Working Group s recommendation to look for simpler solutions, has encouraged us work on accident control and saving commuters time especially at traffic junctions and pedestrian crossing. t. Delay at traffic signals are viewed as invisible speed breakers by the Vehicular commuters. u. Citizen are reluctant to take Public Transport, due to uncertainty, lack of parking place, high parking fee. v. Investment on individual vehicles is costly w. Cost of private transport is comparable to individual vehicle use. x. Roads are poorly maintained. y. Pedestrian express displeasure to take walk-way, under-way and ask for escalator or lift. z. Increased speed would result in severity of accidents. 15

17 Summary of Findings relevant to Traffic Management: 1. The number of conflict points (Crossing Number of its graph) of 4- leg intersection is 16, and that of Pedestrian Crossing is 4. Larger Crossing Number indicates that larger accidents are likely to occur. 2. The signals at intersection operate in FOUR phases and that of Pedestrian Crossing in TWO Phases. Larger number of Phases results in larger loss of time and fuel. Low average speed. 3. The fuel wastage (during waiting for signals)for Vehicular commuters is for 3 phases of the traffic signals 4. At any point of time, commuters of 3-legs will be present at the intersection contributing pollution. 5. Each leg commuter will wait for a duration of 3 phases of the signals contribute pollution. 6. The Signals at Pedestrian Crossing operate in TWO phases. Vehicular and Pedestrian commuters are made to wait for a duration of ONE phase of the signal. 7. Crossing Number is the indicates the number of phases the traffic signals will operate. 8. Thickness of the Graph indicates the number of layers the road system needs to be free from accidents. 9. People using public transport (Pedestrian), cross the road two times in a trip. Thereby, increased use of public transport results in increased number of pedestrian crossing the road (two times in a trip). 16

18 10. Citizen are hesitant to use Public Transport due to lack of parking place and lack of last mile transport facility. Statement of the problem : A large number of accidents are encountered at Major urban centres [1] ; A lot of time is lost at Traffic Signals at intersection and Pedestrian Crossing[2]; fuel wastage due to number of stop and start operations [3], idling at the traffic signals[4]; Increasing cost of transportation results in increased cost goods and services[5]. It is found that the traffic signals are applied more as restraint measure than facilitating traffic movement, thus need improvement[6]. The bar on entry of goods vehicles during the day increases cost of living[7] and resulting in wastage of time results in economic loss[8]. As much as 70% of pollution is attributed to traffic and Commuters are exposed to a large vehicular emission resulting in health problems[9]. Their average speed is found far below the capacity of the vehicles they use [10]. India depends mostly on imported Petroleum products, and our balance of payment situation is in strain. To discourage its use of imported petrol, taxes are levied imported fuel. It is said that the taxes levied to a tune of 40-50% of the cost[11]. The infrastructure creation by way of widening of roads, constructing flyovers, installing traffic signals and employing traffic signals at intersections and pedestrian crossing are giving only temporary relief and increased vehicles are occupying the space created[12]. The signals at traffic intersections and pedestrian crossing are termed as invisible speed breakers by the vehicular commuters[13] and 17

19 road crossing is scaring the pedestrian more lives are lost in accidents than ailments. More young people lost life than the aged.[14]. Loss of hundreds of productive hours in traffic snarls has been recorded world-wide[15]. The Comprehensive Traffic Studies undertaken in India also at Metro cities also. For instance, In Bangalore, an average person lost 272 hours in year due to traffic jam was documented. VIP movements, Ambulance movement are affected due to Jam and special arrangements are needed shows the position of traffic problem[16]. Working professionals complain that they spend 2 hours to reach office which is 30 k.m. away. Person leaving home is doubtful to return, due to high incidence of traffic accidents[17]. Urban is place where agricultural activity is low and is understood as a place for industries, trade and commerce. A Place of high density of population. Has ample facilities for employment, education, health care and recreation. It is also understood as a place of comfort, with facility of residential colonies, availability of drinking water, electricity and facility of road, well lit for day night commuting. According to Censes 2011, 31.16% of Indian population live in Urban Centers The term has elaborate meaning for Censes[18] : 18

20 Statutory Town 1. A Municipality, Corporation, Cantonment Board or notified town area where Area Committee has been constituted by Law. 2. A Place whose population is more than 5,000 is called Census Town. 3. Where more than 75% Men engage in non-agricultural activity. 4. Population Density more than 400 per Sq. Km. are called Statutory Towns 5. Urban Agglomeration An urban agglomeration is a continuous urban spread constituting a town and its adjoining out growths, or two or more physically continuous towns together with or without outgrowths of such towns. (Greater UA. Delhi UA). According to 2011 Census[19]: There are 4041 Statutory Towns Census Towns. 475 Urban Agglomerations 981 Out Growths in India. At the Census 2011 there are 7,935 towns in the country. Many of these are part of Urban Agglomeration and the rest are independent towns. The toal number of Urban Agglomerations/Towns, which constitutes the urban fame, is 7,166 in the country. Of those, Class I cities (population more than 1 lakh) are 468 in number. 70% of population live. 19

21 There are 53 urban centers (population more than Ten Lakh) account for 42.6% population. There are Mega/Metro (population of more than a Million), and Mega cities (with population of more than 10 million) Greater Mumbai Delhi UA Kolkata UA 18.4 Million Million 14.1 Million The Class I cities (population more than 1 lakh) 53 cities on priority list for safe, smooth urban mobility as large number of accidents and loss of valuable time of commuters, at traffic signals are: The road structure of any town constitutes, intersections and roads, where pedestrian and vehicular commuters move. Improved standard of living and availability of motorized vehicles, resulted in acquiring 2,3 and 4 wheelers for personal use. Thereby, traffic Jam/Congestion, accidents, pollution are high. Many a pedestrian lost life due to traffic accidents. Intersections where traffic is not supervised by policemen or signals record accidents and traffic jam is common [22]. Pedestrian cross the road without signals are prone to accident and death. Where traffic signals are provided, vehicular commuters are complaining of low average speed and loss of valuable time [23]. 20

22 Congestion or jam is the impedance and delay imposed by one vehicle on another [24]. When congestion occurs, due to wastage of fuel and time the cost of transportation increases [25]. Delay to people, freight results in increased cost of goods and services. The cost of maintenance of vehicles also increased. The situation demand higher driving skills and alertness[26]. The vehicular pollution increased, there by the health of the commuters is affected due to pollution. The accidents are due to two vehicles trying to occupy same spot, while their paths cross one another [27]. The point of crossing is called conflict point. Higher the number of conflict points higher will be more scope for accidents. To avoid a crash drivers are required to regulate their speed, change direction or stop. Thereby, the vehicles that follow them are forced to do so resulting in congestion or jam and when drivers fail to control results in accident. The Crossing Number of the Graph indicates the number of conflict points encountered. To regulate accidents, traffic signals are introduced [28]. While they are very useful, the time loss at the signals is found to be unbearable and vehicular commuters complain that their average speed has fallen drastically[29]. Road Accident deaths Urban Centers: The loss of life is so severe that a person going out for work, is doubtful of returning. The traffic jam is frequently referred as hell in daily news paper terms. A a result of Jam commuters are exposured to a large 21

23 vehicular exhaust causing ailments and there are reports that people dye two days early fore each day of exposure to vehicular pollution. [30]. According to Guardian, in its report on Road Safety Fund, Traffic accidents are biggest killer of young people worldwide, Roads are now the biggest killer of young people over the age of 10, with road traffic deaths contributing a global health epidemic that has reached crisis proportions, according to Safe and Sustainable Roads report, launched by Campaign for Global Road Safety. The report blames the high numbers of fatalities on transport policies that put vehicles, highways and speed before people and road safety. The vast majority of those who die are in developing countries, with 20 countries accounting for 70% of global road deaths. Traffic Congestion : The Urban Problems [31] There are two main problems that modern day cities face, viz., urban decay when parts of the city become run down and undesirable to live in, and traffic congestion. Traffic congestion is caused by: a. Large number of people work in central part of the city, which may have narrow streets. b. Shortage of off-street parking which means people park on the roads and so increase congestion. c. People not using public transport either because it is less convenient, too expensive or not available. d. More people own and use cars. ( 22

24 Speaking about the traffic jams, the website further says[31]: As an example of how bad traffic ams now are, a hundred years ago it took about one hour to travel from Paramatta to the centre of Sydney (Australia) by horse and cart. Today it takes longer by car. A complete solution to traffic congestion needs people to be able and willing to travel on public transport more, the web-site opiones. Speaking about unreliability in planning a trip, the website says [31]: The Planning Time Index (PTI), a measure of travel reliability, illustrates the amount of extra time needed to arrive on time for higher priority events, such as an airline departure, just-in-time shipments, medical appointments or especially important social commitments. If the PTI for a particular trip is 3.00, a traveler would allow 60 minutes for a trip that typically takes 20 minutes when few cars are on the road. Allowing for a PTI of 3.00 ensure on-time arrival 19 out of 20 times. Shows the uncertainty involved due to congestion/traffic jam Narrating about fuel wastage, the report of 2011 says [32]: Congestion wastes a massive amount of time, fuel and money. In 2011: a. 5.5 billion hours of extra time (equivalent to the time businesses and individuals spenda year filing their taxes) b. 2.9 billion gallons of wasted fuel (enough to fill four New Orleans Superdomes). 23

25 c. $121 billion of delay and fuel cost (the negative effect of uncertain or longer delivery times, missed meetings, business relocations equivalent to lost productivity and direct medical expenses of 12 average flu seasons). d. 56 billion pounds of additional carbon dioxide green house gas released into the atmosphere during urban congested conditions. e. 22% of the delay cost was the effect of congestion on truck operations. Speaking on delays, Suffered 6 hours of congested road conditions on the average weekday in areas over 3 million population, Fridays are the worst days to travel. The combination of work, school, leisure and other trips mean that urban residents earn their weekend after suffering over 20 percent more delay hours than on Mondays. Approximately 37 percent of total delay occurs in the midday and overnight times of day when travelers and shippers expect free-flow travel. [33] Pollution: According to Pollution Control Boards report [34], 50% of air pollution is attributed to emissions from motorized vehicles. By this, life expectancy erodes by two days for each day of exposure to pollution. The health effects associated with pollutants due to vehicular emission are as follows: Carbon Monoxide: Affects the cardio vascular system, exacerbating cardiovascular disease symptoms, particularly angina, may also particularly 24

26 affect fetuses, sick, anemic and young children, affects nervous system impairing physical coordination, vision and judgments, creating nausea and headaches, reducing productivity and increasing personal discomfort. Nitrogen Oxides : Increased susceptibility to infections, pulmonary diseases, impairment of lung function and eye, nose and throat irritations. Sulphur Dioxide : Affects lung function adversely. Particulate Matter : Fine particulate matter may be toxic in itself or may carry toxic (including carcinogenic) trace substance, and can alter immune system. Fine particulate penetrate deep into the respiratory system irritating lung tissue and causing long tern disorders. Lead : Impairs liver and kidney, causes brain damage in children resulting in lower IQ, Hyperactitity and reduced ability to concentrate. Benzene : Is toxic and carcinogenic. Excessive incidence to Leukemia (Blood Cancer). Hydrocarbons : Potential to cause cancer. Much of air pollution is attributed to vehicular emission (and the use of facile fuel). The Carbon oxides, Nitrogen Oxides, Sulphur Oxides, Hydrocarbon and suspended particular matter are the five pollutant contribute to 90% of air pollution. They react with atmosphere and result in Sulfuric Acid, Nitric Acid and Carbonic Acid. Carbon monoxide is produced when organic materials like gas, coal, wood are incompletely burnt. Vehicular exhaust is a major contributor of Carbon Monoxide, as 25

27 they are not properly maintained. Nitrogen Oxide is found in vehicular exhaust which results in secondary pollutant like Ozone. Hydrocrabons pollute air are due to evaporation of fuel or when it is not burnt completely, which when washed by rain run into surface water on reaching with acids like Sulphuric Acid, Nitric Acid, Carbonic Acid is harmful to health. Improved engines can control hydrocarbon exhaust to a large extent (4- stroke engine, improved automobiles). High levels of Lead in vehicular emission is also a cause for pollution. It is evident that incomplete burned fuel and presence of Nitrogen, Sulphur Carbon, Lead in vehicular emission is cause of concern. Pollutants in air cause irritation to respiratory track in human, causing sneezing and cough. Prolonged exposure may lead to cancer, Asthma, Chronic bronchitis. Sulphur oxides irritates respiratory tissues; continuous exposure cause condition cause bronchitis and reaction with water from Sulphur containing acid, very corrosive to lungs. Nitrogen Oxides can irritate lungs lead to Bronchitis, influenza or common cold. Volatile organic Compounds (Benzene and formaldehyde, lead Cadmiumn) cause reproductive problems and Cancer. Effects on Plants: Gaseous pollutants enter leaf pores damage plants, Chronic exposure breaks down waxy coating leads to damage of plants are prone to disease 26

28 turns leaves yellow, brown or higher concentration of Sulphur dioxide turns flower buds stiff and hard, cannot bloom. Noise Pollution and its effects on Physical and Mental Health [36]: Noise upto 80 db (Decibel) are harms. Workmen exposed to db sound at work place developed temporary threshold Shift. 50% of them faced noise-induced permanent threshold shift. Most people exposed to 105 db sound faced permanent hearing loss of some degree. Factories with noise machinery, workers are subjected to high sound levels for several hours a day. Exposure to 95 db for 8 hours every day for over a period of 10 years may suffer noise-induced permanent threshold shift. The excessive sound levels can cause harmful effects o the circulatory system by raising blood pressure and altering pulse rates. Noise can also cause emotional or psychological effects, such as irritability, anxiety and stress, lack of concentration and mental fatigue. High decibel sound at intersection for long duration will have significant health hazard to commuters. The Pollution due to vehicular exhaust at intersection and Pedestrian crossing signals are large since they do not switch-off the engine, as they want to move, once green signal is given. The commuters are directly exposed to the vehicular exhaust for a large duration. It is common to see a handkerchief, scarf tied around the face to protect themselves. Traffic signals introduced to control traffic, to free them by accidents, has resulted in stopping the commuters at traffic signals. Thereby, each commuter is 27

29 stopped for duration of 3 signals, and allowed to pass in the fourth. At any point of time commuters of 3-legs are in waiting in the area of intersection, each idling their vehicles, leave vehicular emission. All those present at intersection, including policemen and pedestrian are exposed to this emission, thereby suffer cardiovascular diseases. There is every need to minimize the intensity and duration of such exposure. The Urban Centre consisting of road crossings and through roads, congestion occurs at 4-leg intersections and pedestrian crossings[37]. Traffic signals are introduced to facilitate smooth flow of traffic. The signal at In a 4-leg intersection operates in four phases and people of each leg are forced to wait for a duration of 3 phases out of 4 phases[38]. Again, at any point of time commuters of 3 legs of intersection will be waiting for signal[39]. Again, each commuter is exposed to vehicular exhaust for a duration of 3 phases of signals to the vehicular exhaust by 3 leg commuters[40]. Review of approaches to Urban Mobility. International agencies like World Bank, Unesco, has expressed great concern over poor mobility conditions encountered by Urban Centres, affecting economy and health hazard [41]. Our National Government has also attached priority to Urban Mobility, of safe, secure and smooth mobility, in the form of five year plans[42]. A Working Group has been constituted for dealing the issue of increasing accidents, pollution [43]. 28

30 The problems of Traffic Management are encountered worldwide. Both Developed countries and developing countries like India encounter problem of accidents, loss of time due to congestion and as waiting time at traffic signals. The Texas Transportation Institute [44], in its recent report said Driven Apart: How sprawl is lengthening our commutes and why misleading mobility measures are making things worse has also added that the solution to congestion problem has much more to do with how we build our cities than how we build our roads means that the measures are not resulting in sizable results. The World Bank also has examined the problem [45]. The valuable time lost in traffic congestion, loss of lives due to traffic accidents, pollution resulting on account of vehicular emission was documented. The approach of road widening and construction of flyovers at high cost, Mass mobility solutions were examined by experts. They were assessed to bring temporary relief but not complete solution, is due to proliferations of vehicles added to the roads, due to improved standard for living. The created extra road space is not sufficient and the problem of congestion, accidents are continue to occur. Recognizing the problem, Government of India, has announced a National Urban Transport Policy In the year 2006 [46]. A Working Group has suggested several measures of infrastructure creation like widening of roads, construction of flyovers, road over bridges and subways for pedestrian use. Have also examined the methods of Mass transport measures like Multi Model Transport System, Bus Rapid Transport System, Light Rail, followed world wide and concluded that they have not resulting in good results, and hence are to be adopted after careful analysis. Experts of Transportation cautioned 29

31 that they will push the country into further debts. The World Bank in its report Cities on move has also considered the issue and felt that the approaches are not bankable and discouraging financing [47]. Finally, the Working Group has examined the matter and suggested that new methods of Urban Mobility have to be evolved and offered some suggestions. After the recommendations of the Working Group, the Ministry of Urban Transportation [48]has designated four Centers of Excellence and spelt out the areas of work: a. IIT Delhi - Public Transit Planning, design and optimization with special focus on BRTs, Integration of Urban Planning, Traffic Flow, use of ITS, impact/benefits to environment including Non-Motorised Vehicles and Road safety factors in Urban Areas. b. IIT Chennai ITS application in Urban Areas, Urban Transport Systems Planning and Urban Transportation Infrastructure Management. c. National Institute of Technology, Warangal Strategy for improving Mass Transit Patronage, Modeling Urban growth Land use, Transport Integration and development of Capacity Analysis for Urban Streets. ITS based Traffic and Road Safety Management System and Modeling & Mapping Environmental Pollution. d. CEPT University, Ahmadabad Land use Transport Integration, Transit Oriented Development, BRT planning and management, Fiscal tools for Urban Transport Management, Transit Impact Assessment, Social and Environmental aspects of urban transit and Sustainable Urban Transport. World over the problem of accidents, traffic congestion are tackled by introducing infrastructure of flyovers, wider road structure and speed mobility solutions. Imposing restraining measures viz., speed limits, traffic signals to regulate pedestrian and vehicular traffic, exclusive lanes for public transport, cycle lanes. The 12 th Plan document of Government of 30

32 India [49], has prepared a policy framework for a five year period of , has given some recommendations, wherein it was stated that Cities and Towns contributed to more than 60% (approximately two-third) of the total Gross Domestic Product. Spelt out an approach to be followed, recognizing For the cities to remain livable, bankable and as engines of economic growth, it is utmost important that the urban mobility issues are effectively addressed and the present gridlock in most of the big urban agglomerations is immediately taken care of [50]. Referring to National Urban Transportation Policy-2006, the Working Group has set 10 goals giving certain guidelines : a. To create facilities for walking and cycling (in cities with population more than 2 lac) with an intention of encouraging non-polluting modes of transport. b. To develop non-polluting mode transport network for last mile connectivity, to improve employment potential. c. Introduction of organized bus service (public transport) for cities with more than 23 lac population (to control pollution). d. Providing Bus Rapid Transport System at 20 km per 1 million population (in 51 cities with population more than a million). e. Provide rail transit at 10 km/million population in phased manner: i. Provide rail transit at 10 km/million population at cities with population more than 2 million; first in cities with population more than 3 million. ii. Expand rail transit in Maga cities (more than 4 million population) at 10 km per year (50 km in 12 th plan period. iii. Provide suburban rail services in urban agglomerations with population more than 40 lakh. 31

33 f. To improve accessibility and mobility in cities by developing hierarchical road network in newly developing areas; completing major road network projects. g. To improve and maintain road surface to the highest standard with good drainage facility (repair work). The Traffic Jam, loss of valuable time at traffic signals, accidents at intersections without signals, pollution at traffic signals, cost of infrastructure, for urban mobility are inter dependant and need careful approaches to tackle them. If we prevent accidents using traffic signals, valuable time of commuters is wasted for waiting at signals, They are exposed to large vehicular exhaust causing ailments. There average speed falls drastically and pollution due to vehicular exhaust are encountered resulting in health hazard. If we encourage vehicular speed, pedestrian suffer accidents. When roads are widened to accommodate vehicles waiting at signals, pedestrian have to walk large length of the roads, take more time, forcing vehicular commuter wait longer. Vehicular commuters suffer more exposure due to pollution, loss of fuel during waiting time. If we restrict goods vehicles during day time, to control accidents, the cost of goods increase due to increase of cost of transportation. If we encourage use of Public Transport to discourage individual vehicles, the pedestrian crossing the road is increasing and more pedestrian suffering accidents. The investment on Buses and Rail is enormous and cannot be undertaken by Goverment and people are to be taxed in the name of Use and Pay. Where it 32

34 is not possible Public Private Partnership and levying Toll has to be resorted to. Pleople are preferring Public Transport for lack of last mile connectivity and lack of or costly parking fee. Lack of security to vehicle and fuel. In view of high density population of our cities, unplanned city expansion, our cities are specific in the sense, there is a by-lane every 10 meters, bus stops every 500 meters and large number of pedestrian crossing the road. Large number of intersections traffic control, in form of traffic signals. Our cities do not have distinction of road and street, where roads are widened, pedestrian have hell visible, the road dividers running along the road from intersection to intersection, donot permit crossing road and pedestrian are in their anxiety to cross the road suffer injury or death. Where pedestrian crossings are provided, the vehicular traffic complain of longer delays as pedestrian take long time to cross the road, since the roads are upto 100 feet now. It is burden for both pedestrian and vehicular traffic. The number of traffic Signals on their path, large time is wasted at the signals and they are exposed to pollution which cause health hazard. The large number of accidents go un recorded, pollution pose a major problem to commuters. The signals installed to control accidents at intersection and pedestrian crossings, are consuming large time of vehicular commuters and they complain that signals have become invisible speed breakers and they are put to huge pollution while waiting for the signals. Much of fuel is being wasted during waiting time, if the same is used for commuting it helps economy. 33

35 On the whole I feel accidents and time loss at traffic signals are major culprit for urban mobility problems and once it is tackled other problems of wastage of fuel, low average speed, pollution will be solved to a major extent. Accordingly, an analysis of Traffic at intersection and pedestrian crossing is undertaken to simplify the signaling system. Problem of Accidents [51]: There has been a spectacular increase in motor vehicles has resulted in a major social problem the loss of lives through road accidents. World-wide road accidents are alarming. The situation in India is more verse In percentage terms, persons killed during a year are as follows: Thailand Delhi USA (1994) (1995) (1987) Pedestrian Cyclists Two-wheeler occupants Four-wheeler occupants Others In 1968, the Government of India has set up a Study Group to assess accident situation in India. Another Committee on Road Safety submitted its report in The Prakash Narain Report for the Planning Commission (2001) has recommended setting up Trauma Care Centres. Shows the important attached to accidents suffered. 34

36 At the International level, organizations such as World Health Organisation and Economic Commission for Europe publish statistics of road accidents[52]. The Road Research Laboratory (U.K.) has been publishing figures on accidents since 1963, Smeed and Jeffcoate, have presented accident figures of 68 countries, which include India, early in , in their report to Organisation for Economic Co-operation and Development, Paris, The number of persons killed per 10,000 vehicles is high for India, which is 24[53]. Traffic Signals : Traffic signals are used to control conflicting streams of vehicular and pedestrian traffic. The first traffic signal is reported to have been used in Land early in The advantages of Traffic Signals are as follows: a. They offer orderly movement of traffic. b. Improve capacity of the intersection/pedestrian crossing. c. Reduce frequency of accidents (right-angle type and pedestrian) d. They can be coordinated to provide continuous or near continuous movement of traffic at definite speed. e. Can be used to interrupt heavy traffic, to permit others. f. Substitute Police for control. g. They offer orderly movement of traffic. h. Improve capacity of the intersection/pedestrian crossing. i. Reduce frequency of accidents (right-angle type and pedestrian) j. They can be coordinated to provide continuous or near continuous movement of traffic at definite speed. k. Can be used to interrupt heavy traffic, to permit others. l. Substitute Police for control. 35

37 Disadvantages of Traffic Signals: a. Excessive delay to vehicles (at peak hours). b. Unwarranted signal installation results in tendency of signal jumping. c. Drivers are induced to take alternate route (less safer route), to save time. d. When signals are faulty/breakdown, widespread confusion, difficulty are faced. Driver is the key factor in most of the accidents. He is the human element in charge of the vehicle. He drives, steers, accelerates, decelerates, brakes and stops, Any error in judgment results in crash. His skill in driving, his emotional make-up, condition of the vehicle all play a vital role in safety. Age and Sex of driver have also been found to be important factors in safety. In the course of driving, Driver has to overtake many vehicles and be overtaken by some, perform numerous turning, ability to comprehend dangerous situations at intersections, deal with a number of pedestrian who cross the streets at all sorts of odd places. He is required to make many important decisions in a fraction of second. Drivers job involves a great risk to self and commuters. He encounters a great stress. There by accidents are more at intersections and when pedestrian cross the road. According to TRIPP (Transportation Research and Injury Prevention Programme) report by Shri Dinesh Mohan There is still no clear vision among planners, policy makers and transport experts about what cities in India need and what will make them 36

38 better places to live in as far as mobility and access are concerned. The prevailing mythology is that construction of metro rail systems will somehow solve problems of the future and this remains the single one point agenda of almost all transport consultants in India. Unfortunately, the fact is that underground or elevated rail (or road) systems have not solved any of the problems of congestion, pollution or of access for a majority of city residents in any city in the world, especially new cities {54} The problem requires a fresh look. Accordingly, I have decided to examine the problem afresh from Topological Graph Theory approach to minimize accidents, control loss of time and fuel and the exposure to vehicular pollution at Urban Centres. 37