Journal of Engineering Sciences, Assiut University, Vol. 39 No 2 pp.283 -299 March 2011
EVALUATION AND ANALYSIS OF URBAN PASSENGERS
TRANSPORT MODES OPERATION PERFORMANCE &
EFFICIENCY
Owais M, M1, Salah G, Oneib M2, and Abbas, Y3
1
Demonstrator, 2Assistant Professor, 3Professor
Civil Engineering Department, Assiut University, Assiut, Egypt
(Received February 19, 2011 Accepted April 2, 2011)
While the demand for transportation is growing rapidly, many problems
are facing planners and traffic operators in urban areas; such as; low
performance and efficiency levels of passengers transport system. The
strategy for tackling these problems has been for years to consider
adding more capacity to the transport supply system, through huge
investments in transport infrastructure. Best utilization of available
transport services and facilities is an urgent necessity. Methods
developed in the theory of optimization, through making use of advanced
computation technology, would allow one to make experimental analysis
and evaluation of different policies and strategies for better
understanding of the transportation problem and to select a solution for
efficient utilization of resources.
This paper presents a methodology for transport modes operation
analysis for different policies and strategies to be simulated in order to
reach optimal goals. The performance and efficiency of transport modes
operation are formulated in a framework as an output maximization
process of an objective function, subject to state variables, decision
variables, constraints and variable bounds. Four main traffic operation
strategies which would have great impacts on urban transportation
performance and efficiency were analyzed, each strategy contains
heuristics of many trial values of decision variables. The overall
methodology is seeking global optimality.
The research output revealed two important indicators for alternative
transport systems evaluation; Mode Efficiency Factor and transport
system passenger supply Efficiency Index. The efficient transport system
supply that satisfies a certain demand is attained. Moreover, an
identification and clarification of most compatible transport modes,
suitable for passenger demand sharing, that would give optimal
performance indicators are documented.
KEYWORDS: Urban passengers; Transportation Modes;
Optimization; Operation Performance; Operation Efficiency
1. INTRODUCTION
Most cities all over the world are suffering from acute traffic problems causing
congestion, slow of movement and environmental drawbacks, due to increasing carownership, growing economy, growing travel demand. Transport mobility and easy of
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access in urban areas are a necessity for promoting and growing economic expansion
and development. The provision of transport supply is limited by funding
insufficiency; also transportation facilities cannot increase in short period to match the
growing demand. Therefore, best utilization of the existing facilities; i.e. enhancement
of the existing transport system performance and efficiency is an urgent need [UITP,
1991]. The transportation efficiency can be defined as: the extent to which a certain
transportation input can meet the travel demand of people in a transportation system
[Yuan & Lu, 2005].
Transportation problem is a combination of vehicles, route, economics,
computation technology and mathematical optimization [Fusco, et. al, 2002]. Traffic
management seeks to improve movement of people and goods, not necessarily
vehicles, by contributing to the improvements of the traffic related environment.
Traffic management aims to adjust, adopt, manage and improve the available
transportation services and facilities to meet specified objectives without restoring to
new infrastructure constructions. It involves development and use of physical and
policy measures to achieve the most efficient use of traffic services and facilities to
meet passengers demand at low cost solution to the problem [Cracknell, 2000; OECD
,1995].
Traffic congestion management measures are usually considered as
(demand/supply) types [Paulley et. al, 2006]. "Demand side" measures are designed to
reduce car demand on the system by increasing vehicle occupancy, reducing the need
to travel during peak periods or reducing the need to travel specific locations by proper
land use planning. “Supply side” measures are designed to adopt increasing public
transport performance, policies and measures that enables efficient utilization of
existing facilities and services (supply based strategies) [Paulley et. al, 2006].
Optimization models are used widely in most areas of decision-making, such
as engineering design and financial portfolio selection [Arsham, H., 1994]. A
mathematical optimization model consists of an objective function and a set of
constraints in the form of a system of equations or disparities. Methods developed in
the theory of optimization making use of advanced computation technology; would
allow one to make experimental analysis and evaluation of different policies and
strategies for better understanding of transportation problem and to select solutions for
efficient utilization of available resources [Borndo et. al, 1998].
This paper presents a methodology for transport modes operation analysis for
different policies and strategies to be simulated to reach optimal goals. Transport
modes operation performance and efficiency variables are formulated in a framework
as an output maximization process of objective function, subjected to state input
variables, decision variables, constraints and variable bounds.
2. URBAN TRAFFIC OPERATION PROBLEM DESCRIPTION
AND CATEGORIZATION
For small networks as the case of medium size cities, passengers demand is grouped
into traffic zones. Each zone has been associated with; one zone centroid, group of
passengers with their associated Origin / Destination (O/D) trip desires which are
concentrated at zone centroid. Transport modes supply services of given vehicles
carrying capacities are routed in an environment to pick-up and deliver passengers
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285
demand. Selection of best route (trunk route) is done by deterministic methodology
guided by criterion. One would propose an algorithm that selects a route on the base of
shortest path that connects pairs of terminals and serves the greatest number of (O/D)
pairs. Route generated is jointed at main nodes (Zone-centroids) [Pages et. al, 2006].
The scope of research is a practical methodology to identify route and
associated passengers' modes, flow rates to serve demand and that leads to minimize
overall transport system costs. In this case transport problem is solved as static
problem, since each zone pair is taken independently. The problem treated is stochastic
in nature, both in terms of network conditions and in future occurrence of demand
points. A possible way to tackle the entire problem would be to solve in different
stages through discrete mathematics and optimization process. This approach leads to a
better understanding of transportation system.
3. PROBLEM FORMULATION
The aimed approach is to develop a procedure for urban passengers transport modes
operation through discrete mathematics and optimization to achieve the most efficient
use of transport services and facilities to meet demand at minimum overall transport
costs.
Dynamics of passengers transportation problem add a level of difficulty
(compared to static problem), mainly when the demand is not known in advance. A
possible way to tackle the problem would be to solve it as a static one in different
stages through discrete mathematics and optimization process, each zone pair is taken
independently.
Static case is used when the dimensions of the problem is small (like the case
of medium size cities) [Pages et. al, 2006]. That scheme does not consider passengers
behavioral models (modal split is assumed given).
In a current problem solution; passengers are assigned to use modes at
proposed passengers' shares (Decision variables). The road passengers transport
problem fits into category of optimization problem in which passengers have to be
assigned to transport services and facilities fulfilling some constraints to achieve the
most efficient use of transport system facilities and services.
The main elements of constrained optimization process are:
1. Basic Input Data Module: This would require data such as; vehicles type,
vehicle characteristics and road link (segment) characteristics.
2. Decision Variables Module: Decision variables which influence the level of
transport system performance and efficiency these would require data such as;
- Vehicle carrying capacities, vehicle flow rates, etc.
- Assigned passengers share (%) to modes.
- Assigned mode priority.
The values of variables are not known when one would start the problem
solution. Decision variables mean; if (value) is included in the solution, the (result)
corresponding decision variable is (so).
3. Objective Function Module: It measures the desirability of a feasible solution
that is a single number associated to every solution, (time, cost, passengers); solving
the problem means to find such a best solution. It is a mathematical expression that
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combines the goals; (maximizing productive activity) (pass./hr/km) or (minimize
overall transport costs).
4. Constraints Module: These are mathematical expressions that combine the
variables to express limits on possible solutions; such as (desired level of service,
link practical capacity constraint).
5. Variable Bounds: Variables usually have bounds not to be exceeded in the
analysis process.
Problems are represented by mathematical models in which objective function
is linear and constraints are given by linear equations, Linear Programming (LP) is
used. If the relationships between variables are not linear functions, non linear
programming methods are necessary. LP is most extensively used as a major technique
for constrained optimization "planning using linear models". LP uses the simple
method with bounds on variables. Model is based on the idea of "space" feasible
solutions (all possible results of the planning process) [Watson, 2010]. Feasible
solutions are not known, they are described implicitly by means of so-called
constraints.
The mathematical expression of objective function and constraints are linear as
follows:
Objective Function:
Maximize:
C1X1+ C2X2+………… CnXn
(1)
Subject to:
X1 > 0 ,
X2 > 0 , ……….. Xn > 0
(2)
, and Constraints:
a11X1+ a12X2+…………+ a1nXn < b1
a21X1+ a22X2+…………+ a2nXn < b2
.
(3)
.
am1X1+ am2X2+…….…+ amn Xn < bm
Where;
a11 a12 . . . . . . a1n
b1
b2
a21 a22 . . . . . . a2n
.
.
.
.
.
.
am1 . . . . . am n
bm
Set of known constraints parameters.
X1 , X2 . . . . . . Xn
Set of unknown variables which would be solved by simplex method. The
constraints describe conditions that every feasible solution has to meet, and any value
that satisfies all constraints is considered feasible solution [Watson, 2010].
4. URBAN PASSENGER TRANSPORT PROBLEM
IDENTIFICATION & MODELLING
4.1 Problem Identification
The road passenger transportation problem is an optimization problem in which drivers
should be assigned to transport services, satisfying some constraints and minimizing
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287
some function cost [Lo´pez et. al, 2009]. The road passenger transport problem can be
presented as follows:
1. Transport supply system (services & facilities): links or segments of road
which has the same characteristics, transport modes which share passenger
transport, vehicle characteristics.
2. Passenger demand: passengers would move from origin (i) to destination (j)
(pass./hr).
3. Sets of constraints:
a. All passenger demand is satisfied by supply system.
b. Mode assigned frequency would be ≤ the available fleet size of such mode.
c. Links (segments) capacity constraint i.e; (all traffic vehicles volume) should be
≤ segment practical capacity or a specific value to satisfy a desired level of
service.
4. Operational planning is organized in a sequential process. Some co-ordination
among the different transport modes is provided by a planning hierarchy; that
simply:
a. 1st mode schedules assigned passenger share (%) and or;
b. 2nd mode schedules assigned passenger share (%) and or;
c. 3rd mode schedules assigned passenger share (%)
The intent is to find supply system flow rates to satisfy passengers demand
over such segment a (trunk route) and to provide a maximum level of service at
minimum costs.
The strategic and operative planning play an important role, that has inspired
the development of large number of problems through decision variables (specific
solutions), viewed as rule oriented planning [Lo´pez et. al 2009, Shahin 2006].
The main idea in this work is to organize the process as a sequence of steps at
some (definable) level of detail. An advantage of this sequence is that the planner can
always justify the reached results as a correct outcome of scheme (strategy). This
approach is designed with an eye on desired objectives, a rule oriented decision
process.
4.2 Problem Modeling
One would formulate the services approach in terms of variables, domains, and
constraints with the following steps:
a. Services (variables) required to model the problem.
b. Domain of each mode variable (variable cells).
c. Sorting input data (parameters).
d. Sorting variables (decision variables) services have been ordered according to
initial start or (lower cost mode is tried first).
e. Sorting constraints.
4.2.1. The objective function
The objective function is defined as following:
Maximize (productive activity) = T [ ∑i ∑j ∑k (Xk * Ok) ]
Where: T = time duration, one hour is assumed.
Xk = vehicle service rate frequency (veh./hr),
(4)
Owais M, M , Salah, G, Oneib M, Abbas, Y
288
Ok = average vehicle passenger occupancy of mode “k” (pass./mode)
i = start point, and j = end point
The objective function mathematical formula implies that the main variables in
the productive activity of a segment are: Vehicle occupancy (pass./mode), vehicle
frequency (veh./hr), desired traffic flow speed (kph), and Segment practical capacity
(p.c.e's/hr).
Route segment is the basic unit of productive activity; is defined as the
maximum (pass./hr) to be transported over a link (segment) of a route one directional
flow at an acceptable level of service
4.2.2. Link (Segment) Constraint
∑i ∑j ∑k 1.15* [ Xk * Ek ] ≤ C where:
∑i ∑j ∑k [ q ] ≤ C
(5)
Xk = vehicle service rate frequency (veh./hr)
Ek = vehicle equivalency factor of mode (k) [p.c.e's]
C = link (segment) practical capacity (p.c.e's/hr)
q = traffic volume (all vehicles) (p.c.e's/hr)
*
Other vehicles (non pass. vehicles) link utilization is considered (15%) of link
capacity.
4.2.3. Traffic Flow Speed Constraint [Wahdan and Sabry, 1995 ;
HCM, 2000]:
Us = Uf [ 1 – α (eβ ln(q/c)) ] or Us= Uf [ 1 - α
(q/c) β
(6)
where: Us = desired traffic flow speed (kph)
Uf = speed limits (one would consider 60kph)
(q/c) = traffic volume/ practical capacity
α , β = calibration factors (best assigned values are: α=0.7 , β= 2.2)
4.2.4. Related Mathematical Analysis Formulation:
i. Supply System Carrying Capacity: (see analysis strategies input data)
Maximize Passenger No. (pass./hr) = O1X1+O2X2+O3X3 (Objective Function)(7)
Subject to; X1 ≥ 0, X2 ≥ 0, X3 ≥ 0
Where X1 = “Priv.+Taxi”
X2 = Micro-bus
X3 = Bus
(vehicle
frequency/hr)
O1, O2, O3 vehicle passenger occupancy of mode (passenger/mode) (input data)
ii. Lane Capacity Constraint [HCM 2000]:
q = 1.15*(E1X1+E2X2+E3X3) ≤ 800 p.c.e's/hr
(8)
Where, E1, E2, E3 are vehicle equivalency factors
iii. Lane Speed Flow Constraint:
Us = 60*(1 - 0.7e2.2Ln(q/800)) ≥ 30 kph
(Level of Service (C))
iv. Fuel Consumption [Abbas, 1998]:
C X +C X +C X
F .C . = 100 * 1 1 2 2 3 3
O1 X1 + O2 X 2 + O3 X
3
(in lit/pass./100km)
Where, O1, O2, O3, X1, X2, and X3 are as defined before.
C1, C2, C3 are fuel consumption of mode (lit./km) (See analysis strategies input data)
(9)
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Supply transport system performance focuses on the degree to which segment
can produce maximum activity at constraints and some environmental restrictions (e.g.;
noise level … etc.).
5. METHOD USED AND ALGORITHM
The algorithm used is divided into the following modules:
- Input data.
- Decision variables.
- Variable cells ↔ variable bound.
- Heuristics (sequential process).
- Mathematical formulation.
- Optimal target cell (maximizing & minimizing).
- Constraints.
- Objective function.
- Output results.
Figure 1 shows the modeling flow diagram. It is important to notice that the
heuristics sequential process is solved once and its solution is used as initial solution
for iterative process, the overall methodology seeking global optimality [Fusco et. al,
2002].
The Solver program tool was utilized for this study. The Solver program tool
uses the Generalized Reduced Gradient (GRG2) optimization. It is used to determine
maximum or minimum value of one cell (target cell) that contained within objective
function by changing the other cells (the parameters of objective function) under
defined constraints [Watson, 2010]. Solver is a part of suite commands called (what-if)
analysis; a process of changing the value in cells to see how those changing affect the
outcome formulas on (the working sheet). It is an iterative numerical method that
involves plugging in trial values for the adjustable cells and noticing the results
calculated by constraints cells and the optimal cell. Each trial is called iteration.
Extensive analysis of the observed outputs and their rates of change as inputs are
varied to guide the selection of new trial values. Solver works with a group of cells that
are related directly or indirectly to the formula in target cell. It adjusts the values in the
variable cells applying constraints or limitations placed in the solving problem.
6. EXPERIMENTAL ANALYSIS OF OPTIMIZATION TECHNIQUE
ON URBAN PASSENGERS TRANSPORT MODES
OPERATION
The developed model contains the principal structural relationships that exist among
the various components involved in overall management of transport system. The user
enters the basic input data, values of key parameters and selects the policies and
strategies to be simulated. The model utilizes all these inputs through its mathematical
formulations, algorithms, traces the requirements. It considers the effects that these
components have on each other as well as on the overall performance of the transport
system.
The following section demonstrates the model applicability in simulating four
defined strategies.
6.1. Analysis Strategies:
Passengers transport structure of urban traffic is the composition of the proportion that
all traffic modes share in total trips in urban traffic system. That is the proportion of all
Owais M, M , Salah, G, Oneib M, Abbas, Y
290
kinds of modes which passengers assign to travel. In urban traffic system all kinds of
traffic modes share the passengers demand. There are great differences for different
modes indicators, such as; carrying capacity, operation flow rate, operating speed,
transportation cost.... etc. [Zang et. al, 2005].
Basic Input Data
Decision Variables
Variable Bound,
≤-≥
Sequential Process
Variable Cells
Mathematical Formulation
Optimal Target Cell
- Maximizing
- Minimizing
Constraints
NO
Yes
Objective Function
NO
Maximum
Productive
activity
Yes
Output Results
Figure 1: Urban Passengers Transport Problem simulation (Modeling Flow Diagram)
EVALUATION AND ANALYSIS OF URBAN PASSENGERS …
291
Four main traffic operation strategies were analyzed. These strategies, denoted
(A, B, C and D) would encompass different modes indicators and have great impacts
on urban transportation system performance and efficiency. Each strategy contains
heuristics of many trials values of decision variables. The over all methodology is
seeking optimal goals. The main elements of each strategy associated by constrained
optimization process (strategy objective, variable cells, decision variables, constraints,
and input data) are given below.
6.1.1. Strategy Objective:
i. Maximizing Transport Supply System Carrying Capacity (pass./hr).
ii. Minimizing overall Transport system costs
6.1.2. Decision Variables and constraints:
The decision variables for each strategy are presented in the following table:
Table 1: Decision variables for considered strategies
Strategy
Decision variables
A, B, C, and D
- Supply Bus Transport fleet frequency varies between 10 and 120
bus/hr.
- The number of assigned vehicles must be ≤ available fleet.
- Micro-bus carrying capacity share percentage is variable (from
optimization process).
- Lane capacity constraint ≤ 800 p.c.e's/hr.
- Speed of Traffic flow (Us) ≥ 30 kph.
- Assigned 1st priority to “Priv.+Taxi” with carrying capacity
passenger share percentage varies (5 - 70)% of total system
passengers' carrying capacity.
- Assigned Demand (Di-j) varies (5000, 4000, 3000, 2000, and
1000) pass./hr.
- Assigned 1st priority to “Priv.+Taxi” with carrying capacity
passenger share percentage varies (5 - 70)% of total system
passengers' carrying capacity.
- Bus & Micro-bus are only allowed in the right lane; “Priv.+Taxi”
are prohibited in the right lane (only public transport lane).
- Assigned 1st priority to Bus Transport with fleet frequency varies
between 10 and 120 bus/hr.
ONLY
strategy A:
ONLY
strategy B:
ONLY
strategy C
ONLY
strategy D:
6.1.3. Input Data (for all strategies):
i. Vehicle Characteristics:
The following passenger transport modes are considered “Priv. & Taxi”, Micro-bus
and Bus modes. Vehicle characteristics were reached from extensive literature reviews
and are shown in the following table [Abbas, 1998; HCM, 2000]. It is worth noting
that since Private and Taxi vehicles would nearly have the same vehicle characteristics,
and for simplifying the analysis, they were assumed as a one vehicle type.
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292
Table 2: Vehicle characteristics [Abbas, 1998 ; HCM, 2000]
Occupancy
Vehicle
Code
Fuel Consumption
P.C.E's
(pass.)
(lit./km)
“Priv. Car & Taxi”
X1
1.5
1
0.12
Micro-bus
X2
10
1.5
0.18
Bus
X3
40
2
0.35
ii. Link (Segment) Practical Capacity (p.c.e's/hr) and Flow Operation:
The link (segment) is a part of shortest route (homogenous section) and considered as a
one-way flow direction, with two lanes (8m) width each. Lane practical capacity is
assigned as 800 (p.c.e's/hr), associated with level of service (C) where traffic flow
speed (≥ 30 kph). Traffic flow operation is considered as one of two cases: (a or b) as
shown in figure2. In case (a) the public transports (Bus and Micro-bus) are assigned to
the right lane. In case (b) all modes are assigned equally to each traffic lane (i.e. 50%
of all traffic modes).
Case (a)
Case (b)
Figure 2: The Link Traffic flow cases
In case (a), analysis is directed to the right lane operation performance; since
left lane would be assigned to “Priv.+Taxi” and other non passenger traffic with full
lane utilization ≤ 600 p.c.e's/hr i.e ≤ 900 pass./hr. Link passenger carrying capacity in
the right lane depends on each strategy results.
In case (b), 50% of all traffic modes is assigned to each lane. So analysis
results of case (a) right lane would be applicable to case (b) associated with public
transport vehicles frequency must be considered 50% and should coincide with case (a)
analysis. Link carrying capacity is lane passengers’ capacity multiplied by (2), other
performance indicators are the same as in case (a).
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293
7. RESULTS AND DISCUSSIONS
For all strategies the following results were attained; transport modes maximum
passenger carrying capacity, traffic flow speeds, fuel consumption, passenger delays,
mode share (%), mode frequency (veh./hr) and lane utilization (%).
Factors which would have strong impacts on transport system operation
performance and efficiency were investigated and analyzed. Also graphical
relationships between these factors and system indicators are given bellow.
Figures 3a, b, c, and d present mode passenger share (%) effect on maximum
passenger carrying capacity. In which, Figure 3a represents “Priv.+Taxi” and Bus
transport modes, Figure 3b represents “Priv.+Taxi” and Micro-bus, Figure 3c
represents Micro-bus and Bus, and Figure 3d represents “Priv.+Taxi”, Micro-bus and
Bus.
(a) Priv. & Bus Modes
(b) Priv. & Micro-bus Modes
(c) Micro-bus & Bus Modes
(d) Priv. , Micro-bus , & Bus Modes
Figure 3: Mode pass. Share (%) vs. Max. pass. carrying capacity (pass./hr); a) Priv. &
Bus, b) Priv. & Micro-bus, c) Micro-bus & Bus, and d) Priv., Micro-bus, & Bus
Modes.
The Efficiency Index “E.I.” of urban transportation systems is the relationship
between the input of an urban transportation system and its capability of satisfying the
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transportation demand in the system. The greater the ratio, the higher the transportation
efficiency is. Transport system Efficiency Index “E.I” = Transport system capacity /
Optimal system capacity
Figure 4 shows the mode passenger share (%) effect on transport system
Efficiency Index “E.I”. In which, the transport system Efficiency Index decreases
rapidly as Private passenger share increases; for example as the Private passenger
share increases from 10 to 15 %, this will cause a decrease in the E.I by about 19% (i.e
1% increase in Private passenger share will lead to decrease in (E.I) by 4%).
Figure 4: Mode pass. Share (%) vs.
Supply system Efficiency Index (E.I.) for
Priv., Micro-bus, & Bus Modes.
Figure5: Mode pass. Share (%) vs. Fuel
consumption (lit/100km/pass.) for Priv.,
Micro-bus, & Bus Modes.
The following table shows the mode passenger share effect on passenger
transport mode maximum carrying capacity pass./hr for strategies A, C, and D. The
Optimal transport system passenger carrying capacity is equal to 7177 (pass/hr) and
can be achieved form strategy C.
The Maximum transport system passenger carrying capacity as well as the
minimum fuel consumption (lit/100km/pass.) can be attained from decision variables
associated with modes passenger sharing (%) as shown in sequence process mix:
- “Priv.+Taxi” passenger sharing (%) varies between (0-5)%
- Micro-bus passenger sharing (%) varies between (15-30)%
- Bus passenger sharing (%) varies between (70-80) %
Table 4 presents the passenger demand level as was presented in strategy (B).
The private passenger share increase (10-15) % associated by demand level.
In strategy (B): For assigned passengers demand levels (5000 – 1000) pass./hr,
as to maintain a level of service (C) where Us ≥ 30 kph, the appropriated “Priv.+Taxi”
passenger share (%) would be as shown in the following table:
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Table 3: Mode passenger Share effect on maximum passenger Transport
system mode carrying capacity (pass./hr)
Strategy
C
D
A
Priv.+Taxi “X1” (%)
0
1
5
Micro-bus “X1” (%)
33
29
16
Bus “X1” (%)
67
70
79
Transport System (pass./hr) Carrying
Capacity
7177
6885
6126
System Efficiency Index (E.I) (%) *
100
96
85
The Transport
Modes Passenger
Share (%)
*Transport system Efficiency Index “E.I” = Transport system capacity / Optimal
system capacity
Table 4: The passenger demand level as was presented in strategy (B).
Demand (pass./hr)
5000
4000
3000
2000
1000
34 - 15
44 - 33
52 - 46
57 - 54
59 -58
Us (%) Decrease
56
25
12
5
2
Us (%) Decrease for
“Priv.+Taxi” Pass. Share (1%)
11
5
2.4
1
0.4
Traffic Flow Speed (Us) (kph)
Table 5: Recommended “Priv.+Taxi” Passenger Share (%) for assigned
demand levels (Strategy B)
Assigned Demand (pass./hr)
5000
4000
3000
2000
1000
Recommended “Priv.+Taxi”
Pass. Share (%)
< 10
< 15
< 20
< 35
> 35
Figure 5 shows the mode passenger share (%) effect on transport system fuel
consumption “F.C” (lit/100km/pass.). In which, the transport system fuel consumption
“F.C.” increases rapidly as the Private passenger share (%) increases; for example as
the Private passenger share increase by (10-15)%, this would result in an in increase
the F.C by about 25%. In addition, as the Private passenger share increases by1%, the
F.C would increase by 5%.
Figure 6 shows the mode passenger share (%) effect on traffic flow speed (Us)
(kph). Results demonstrate the high effect of the Private passenger share (%) on the
traffic flow speed, Us (kph); as the traffic flow speed decreases with the increase of the
Private passenger share, associated with demand level.
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Owais M, M , Salah, G, Oneib M, Abbas, Y
Figure 6: Priv. pass. Share (%) vs. Traffic
speed (kph) for different demands
Figure 7: Priv. pass. Share (%) vs. pass.
Delay (sec/pass./km)
Figure 7 shows the mode passenger share (%) effect on the traffic delays
(sec/pass./km). Results show the high effect of the private passenger share (%) on the
traffic delays; associated with passenger demand level (pass./hr).
8. CONCLUSIONS
Urban transport system operation performance and efficiency are the key indicators
which determine the capacity and satisfaction of the transport system to meet desired
travel demand. To improve the system operation performance and efficiency; the best
way is to utilize effectively the existing services and facilities, through efficient
operation policies.
The aimed approach of this research is to develop a procedure for urban
passengers transport operation; through discrete mathematics and optimization
techniques to achieve the most efficient use of transport services and facilities.
In this research experimental analysis using optimization techniques on urban
passengers transport operation, through developed algorithm containing the principal
structural relationships that exist among the various components involved in the overall
management of the transport system.
Four main traffic operation strategies having great impacts on urban
transportation system operation performance and efficiency were analyzed.
Analysis of the results is shown as relations between various parameters to
transport system operation indicators and is presented through graphical relationships.
The main element having impact on transport system operation performance and
efficiency is “Priv.+Taxi” passenger share (%).
Key findings of results related to defined strategies are:
1. The maximum transport system passenger carrying capacity (pass./hr) and the
minimum fuel consumption (lit/100km/pass.) resulted from analysis would be
associated with modes pass. share in sequence process mix as follows :
- “Priv.+Taxi” passenger sharing (%) varies between (0%-5%)
- Micro-bus passenger sharing (%) varies between (15%-30%)
- Bus passenger sharing (%) varies between (70%-80%)
EVALUATION AND ANALYSIS OF URBAN PASSENGERS …
297
2. Transport system efficiency decrease rapidly as “Priv.+Taxi” passenger share
increases. For example as “Priv.+Taxi” passenger share increases from (10)% to
(15)%, efficiency index would be decreased by (19)%.
3. Transport system fuel consumption increase rapidly as (Priv.+Taxi) passenger
share increase; e.g. as “Priv.+Taxi” passenger share increase from (10)% to (15)%,
fuel consumption (lit/pass./100km) would be increased by (25%).
4. Traffic flow speed (kph) decrease as “Priv.+Taxi” passenger share increase,
associated with demand level e.g. as “Priv.+Taxi” passenger share increase from
(10)% to (15)%, traffic flow speed would be decreased by: (56)% associated with
demand (5000 pass./hr), (25)% associated with demand (4000 pass./hr), (12)%
associated with demand (3000 pass./hr) etc., with reference to traffic speed at
passenger share at (10)%.
5. For assigned passenger demand levels (5000 – 1000) (pass./hr); as to maintain a
level of service (C) where Us ≥ 30 kph, appropriate “Priv.+Taxi” pass. share
would be as follows:
Assigned Demand (pass./hr)
5000
4000
3000
2000
1000
Recommended “Priv.+Taxi”
Passenger Share (%)
< 10
< 15
< 20
< 35
> 35
6. For high demand levels; >5000 pass./hr passenger delays (sec/pass./km) would be
very high for “Priv.+Taxi” passenger share > 10 % since traffic speed would be
decreased by > 50 (%) with reference speed ≥ 30 kph.
9. ACKNOWLEDGMENT
The authors would like to express their gratitude to Prof. Owais, M.A Prof. of
transportation planning & Traffic Eng., Civil Eng. Dept. Assuit Univ. for his valuable
advice and recommendations which contributed to this research work.
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" " ﺘﺤﻠﻴل وﺘﻘﻴﻴم أداء ﻜﻔﺎءة ﺘﺸﻐﻴل وﺴﺎﺌل ﻨﻘل اﻝرﻜﺎب ﻓﻲ اﻝﻤﻨﺎطق اﻝﺤﻀرﻴﺔ
ﻨظـ ـ ار ﻝزﻴ ــﺎدة أﻋ ــداد اﻝﻤرﻜﺒ ــﺎت وﻤﻠﻜﻴ ــﺔ اﻝﺴ ــﻴﺎرة اﻝﺨﺎﺼ ــﺔ وارﺘﻔ ــﺎع ﻤﻌ ــدﻻت اﻝﻨﻤ ــو اﻻﻗﺘﺼ ــﺎدي وﻜ ــذﻝك وﺒطـﺊ ﻓـﻲ، ﻤﻌدﻻت اﻝﺤرﻜﺔ ﻤﻤﺎ أدي إﻝﻰ ﻤﺸﺎﻜل ﻓﻲ إدارة وﺘﺸﻐﻴل اﻝﻤرور ﻤﺘﻤـﺜﻼ ﻓـﻲ اﺨﺘﻨﺎﻗـﺎت ﻤرورﻴـﺔ
.ﺤرﻜﺔ ﺴﻴر اﻝﻤرﻜﺒﺎت وﺘدﻫور ﻓﻲ أداء وﻜﻔﺎءة وﺴﺎﺌل ﻨﻘل اﻝرﻜﺎب اﻝﺠﻤﺎﻋﻴﺔ و اﻝﺨﺎﺼﺔ
ﺘرﻜــزت اﻝﺤﻠــول ﻓــﻲ اﻝﺤﻘﺒــﺔ اﻻﺨﻴ ـرة ﻋﻠــﻲ ﺼــرف إﻨﻔﺎﻗــﺎت ﻫﺎﺌﻠــﺔ ﻓــﻲ اﻹرﺘﻘــﺎء ﺒﺎﻝﺒﻨﻴــﺔ اﻷﺴﺎﺴــﻴﺔ ﻝﻠﻨﻘــلوذﻝك ﻹﺴﺘﻴﻌﺎب ﻤزﻴد ﻤن ﺤرﻜﺔ اﻝﻤرﻜﺒﺎت وﻝم ﺘﺤﻘق ﻫذﻩ اﻝﺤﻠول إﻻ ﻨﺘﺎﺌﺞ ﻴﺴـﻴرة ﻤؤﻗﺘـﺔ وﺴـرﻋﺎن ﻤـﺎ ﺘﻌـود
.اﻝﻤﺸﺎﻜل اﻝﻤرورﻴﺔ إﻝﻲ ﺴﺎﺒق ذﻜرﻫﺎ
299
… EVALUATION AND ANALYSIS OF URBAN PASSENGERS
ﻴﻬــدف ﻫــذا اﻝﺒﺤــث إﻝــﻲ إﻴﺠــﺎد إطــﺎر ﻋﻠﻤــﻲ ﻴﻤﻜــن ﻤــن ﺨﻼﻝــﻪ اﻝــﺘﻔﻬم اﻝواﻀــﺢ ﻝﻜﻴﻔﻴــﺔ ﺘــداﺨل اﻝﻌﻨﺎﺼــرواﻝﻤدﺨﻼت اﻝﻤﺨﺘﻠﻔﺔ ﻓﻲ إدارة وﺘﺸﻐﻴل اﻝﻤرور وﻨﻘل اﻝرﻜﺎب ﻋﻠﻲ أداء وﻜﻔﺎءة ﻗطﺎع اﻝﻨﻘل داﺨل اﻝﻤدن.
ﻴرﻜز ﻫذا اﻝﺒﺤث ﻋﻠﻲ إﻋداد ﻫﻴﻜﻠﻴﺔ ﻤﺤﺎﻜﺎة ﻓﻲ إطـﺎر ﺘﺤﻠﻴﻠـﻲ ﻤـن ﺨـﻼل ﻨﻤـوذج رﻴﺎﻀـﻲ )(Solverﻗﺎﺒل ﻝﻠﺘطﺒﻴق وذﻝك ﻤن ﺨﻼل رﻴﺎﻀﺔ اﻝﺒﺤوث اﻝﺘطﺒﻴﻘﻴﺔ وﺘﻜﻨوﻝوﺠﻴﺎ اﻝﺤﺎﺴﺒﺎت اﻝﻤﺘﻘدﻤﺔ -أﻤﻜن ﻤن ﺨﻼﻝﻪ
إﺠراء اﻝﻌدﻴد ﻤن اﻹﺨﺘﺒﺎرات ﻝﻨظم ﺴﻴﺎﺴﺎت و إﺴﺘراﺘﻴﺠﻴﺎت ﻤﺨﺘﻠﻔﺔ وﺘﺤﻠﻴل وﺘﻘﻴﻴم ﻨﺘـﺎﺌﺞ ﻓﺎﻋﻠﻴﺘﻬـﺎ ﻋﻠـﻲ أداء
وﻜﻔـﺎءة ﺘﺸــﻐﻴل وﺴـﺎﺌل ﻨﻘــل اﻝرﻜـﺎب اﻝﺠﻤﺎﻋﻴــﺔ واﻝﺨﺎﺼـﺔ وذﻝﻠــك ﺒﻬـدف ﺘﻌظــﻴم اﻝﻘـدرات اﻝﻨﻘﻠﻴــﺔ ﻝﻬـذﻩ اﻝوﺴــﺎﺌل
)راﻜب .ﻜم /ﺴﺎﻋﺔ(.
اﻝﻨﺘـﺎﺌﺞ اﻝﺘــﻲ ﺘــم اﻝﺘوﺼــل إﻝﻴﻬـﺎ أوﻀــﺤت ﺘﻔﻬﻤــﺎ واﺴــﻌﺎ ﻝﻠﻤــدﺨﻼت واﻝﻌﻨﺎﺼـر اﻝﻤﺨﺘﻠﻔــﺔ اﻝﺘــﻰ ﺘــؤﺜر ﻋﻠــﻰأداء و ﻜﻔﺎءة ﺘﺸﻐﻴل و ﺴﺎﺌل اﻝﻨﻘل وﻜذﻝك ﻋﻠﻲ إﻴﺠﺎد ﻤوﺸرات ﺘﻌﺒر ﻋن ﻤﺴﺘوي اﻷداء.
أﻴﻀﺎ أﻤﻜن اﻝﺘوﺼل إﻝﻲ ﻜﻴﻔﻴﺔ ﺘﻌظﻴم اﻝﻘدرات اﻝﻨﻘﻠﻴﺔ ﻝﻬذﻩ اﻝوﺴﺎﺌل ﻤﻤﺎ ﻴﻤﻜن ﻤن اﻹﺴﺘﻔﺎدة اﻝﻤﺜﻠﻲﻤن اﻹﻤﻜﺎﻨﻴﺎت اﻝﻤﺘﺎﺤﺔ وذﻝك ﻓﻲ إطﺎر ﻤدﺨﻼت ﻤﻌﻴﻨﺔ ﻝﺘﺤﻘﻴق اﺸﺘراطﺎت ﺨﺎﺼﺔ.