Total Number Of Vehicles Research Articles

Multi-agent decision system for solving dynamic location in manufacturing cells

This study proposes a new approach to multi-criteria decision support systems (MDSS) using an agent-based approach. The dynamic location /distribution problem is formulated as a mixed integer programming model which forms the basis of the MDSS and whose objectives are to minimize total weighted delivery time, purchasing cost, total weighting cost, or total number of vehicles, by using multi-agent negotiation and cooperation The proposed models and methods are applied interactively to determine the weight of each criterion. The multiple objectives are then transformed into a single objective. A prototype system for delivering goods from multiple suppliers to customers is presented. Since the proposed problem is NP-hard, business software does not work well as the number of suppliers or customers becomes a large (over 100). Thus, a heuristic algorithm is developed and adopted. Compared to the lower bound of the optimal solution, the heuristic algorithm performs well and outputs an adequate solution. An agent-based approach is presented to determine favorable alternatives in changing market environments

Traffic Flow States in a Freeway with Bottleneck

The system of mixture of single lane and double lane is studied by a cellular automata model, which is developed by us based on the Nagel and Schreckenberg's models. We justify that the model can reach a stable states quickly. The density distributions of the stable state is presented for several cases, which illustrate the manner of the congestion. The relationship between the outflow rate and the total number of vehicles and that between the outflow rate and the density just before the bottleneck are both given. Comparing with the relationship that occurring in the granular flow, we conclude that the transition from the free traffic flow to the congested traffic flow can also be attributed to the abrupt variation through unstable flow state, which can naturally explain the discontinuities and the complex time variation behavior observed in the traffic flow experiments.

An agent-based decision support system for solving the dynamic location and distribution problem using multi-criteria decision models

This study proposes a new approach to multi-criteria decision support systems (MDSS) using an agent-based approach. The dynamic location/distribution problem is formulated as a mixed integer programming model which forms the basis of the MDSS and whose objectives are to minimize total weighted delivery time, purchasing cost, total weighting cost, or total number of vehicles, by using multi-agent negotiation and cooperation. The proposed models and methods are applied interactively to determine the weight of each criterion. The multiple objectives are then transformed into a single objective. A prototype system for delivering goods from multiple suppliers to customers is presented. Since the proposed problem is NP-hard, business software does not work well as the number of suppliers or customers becomes a large (over 100). Thus, a heuristic algorithm is developed and adopted. Compared to the lower bound of the optimal solution, the heuristic algorithm performs well and outputs an adequate solution. An agent-based approach is presented to determine favorable alternatives in changing market environments.

The Effect of Driving Restrictions on Air Quality in Mexico City

In 1989, the government of Mexico City introduced a program, Hoy No Circula, that bans most drivers from using their vehicles one weekday per week on the basis of the last digit of the vehicle’s license plate. This article measures the effect of the driving restrictions on air quality using high‐frequency measures from monitoring stations. Across pollutants and specifications there is no evidence that the restrictions have improved air quality. Evidence from additional sources indicates that the restrictions led to an increase in the total number of vehicles in circulation as well as a change in composition toward high‐emissions vehicles.

The Effect of Arbitrary Stopping of Public Vehicles on Flow of Traffic In One–Line Streets

Cellular automaton method was used to simulate the flow of cars in typical streets in Indonesia. In this streets, arbitrary stopping of vehicles at anytime along the streets might happen and violating the traffic regulation by the drivers frequently occurs. This study was restricted to a one-line street passed by two types of vehicles: private car and public vehicles, and a car/vehicle cannot advance the preceding ones (car following model). Arbitrary stopping of public vehicles leads to occurrence of vehicle clustering along the line. The number of main clusters equals to the number of the public vehicles. The total distance traveled by all vehicles during iteration approximates a periodical function, with a period is equal to the stopping duration of the public vehicle. The power spectrum of this movement scales as f -ɑ , with ɑ = 2 and seems to be universal. The distance traveled in unit volume of fuel consumption was also investigated and showed that this distance decreases monotonically when the ratio of public vehicle to the total number of vehicles increases. Key words: Cellular automata; traffic flow; public vehicle; one–line street; fuel consumption

URBANIZATION IN INDIA – A BIGGEST PUBLIC HEALTH CHALLENGE

ISEE-301 Introduction: India, a country with the population of more then one billion is facing major challenges due to rapid urbanization. If the present growth rate continues, by 2026, the total urban population will increase to 506 million from the present figure of 285 million. The population migration from rural to urban areas will contribute the largest share. The authors argue that if no major realistic steps are taken with immediate effect, it will not be long before millions of people face a huge burden of health hazards. Aim: This paper attempts to analyse the current infrastructure, government planning and future policy, and health hazards in Indian urban areas, and to predict future trends with regard to disease burden. Methods: Air pollution, lack of water, sanitation and drainage facilities, vehicular accident, lifestyle disease and mental stress are considered to be the major threats to the health of the urban population. Extensive analyses of reports of census, health information and policy, pollution, urban development, natural resource management along with several research documents have been done. Based on past trends, the future status of urban infrastructure and health outcomes are predicted. The present socio-cultural-political and ecological dimensions from regional, national, and global perspectives are also incorporated in order to make realistic predictions for the coming decades. Results: The present average per capita generation of solid waste and waste water will increase two fold or more in the next two decades, due to changing patterns of life style. Hence, the total per day generation of waste will increase four to five folds during the same period. The present requirement for land for solid waste disposal will increase five to six folds. But due to scarce land resources and the rising population, there will be a severe crisis in solid waste management. The waste water treatment capacity of existing systems will not be able to cope the situation. The medium and smaller towns, not generating major revenue, will face more severe problems due to regional disparity. Global warming and unsustainable irrigation, will lead to a severe shortage of water in rivers and aquifers. The total number of vehicles will increase by six to ten times and poor urban infrastructure will lead to high road accidents and air pollution related health hazards, which will increase by ten to fifteen times. The recent trend of more migration of women will continue, and more vulnerable factors will be entcountered. Growing privatisation and structural adjustments will lead to more inequalities and the poor will bear the brunt, ultimately. Discussion: Considering the present trend, it is estimated that the existing water and vector borne diseases will remain the dominant cause of morbidity and mortality. On the other hand, malignancies, HIV/AIDS, and lifestyle and stress related diseases would emerge as major new challenges. •Complete analysis will be available within a month.

Inserting renewable fuels and technologies for transport in Mexico City Metropolitan Area

This article describes three future scenarios for the potential reduction of CO 2 emissions and associated costs when biogenic ethanol blends and oxygenates are substituted for gasoline, and hybrid, flex fuel and fuel cell technologies are introduced in passenger automobiles (including pickups and sport-utility vehicles (SUVs)) in the densely populated Mexico City Metropolitan Area (MCMA), analyzed up to the year 2030. A reference (REF) scenario is constructed in which most automobiles are driven by internal combustion engines (ICE) fuelled by gasoline. In the first alternative scenario (ALT1), hybrid electric-ICE gasoline-fuelled cars are introduced in 2006. In the same year, ethyl tertiary butyl ether (ETBE) is introduced as a replacement for methyl tertiary butyl ether (MTBE) oxygenate for gasoline. In the second alternative scenario (ALT2), in addition to the changes introduced in ALT1, flex fuel ICE technology fuelled by E85 is introduced in 2008 and electric motor vehicles driven by direct ethanol fuel cells (DEFC) fuelled by E100 in 2013. A comparison between the reference and alternate scenarios shows that while the total number of vehicles is the same in each scenario, energy consumption decreases by 9% (ALT1) and 17% (ALT2), the total non-biogenic CO 2 emissions drop by 15% (ALT1) and 34% (ALT2), CO 2 mitigation cost is 140.14 $US1997/ton CO 2 (ALT2), and ALT1 has savings and is considered a “no regrets” scenario.

ROAD ACCIDENTS IN SPAIN

This report details road accident trends in Spain. According to the report, the number of injury accidents has risen from 79,925 in 1993 to 98,433 in 2002. A number of factors contributed to this rise. For instance, the low 1993 figure is due in part to the introduction in the early 1990s of several safety campaigns. Furthermore, there was a rise in the total number of vehicles during this time, including the number of private cars, motorcycles and industrial vehicles. Changes in population and shifts in vehicular flows must also be taken into account.

Lead content of petrol and diesel and its assessment in an urban environment.

Pakistan is one of the few countries in Asia that continues to use only leaded-petrol as vehicular fuel. The concentration of Pb in its petrol reported in 1991 was the highest (1.5-2.0 g Pb L(-1)) of all produced by the various Asian countries and far exceeded the WHO's guideline of 0.15 g Pb L(-1). We have undertaken a study to trace and quantify this toxic element in the environs of Karachi. Pakistan's major metropolis, having more than 30% of the nation's total number of vehicles. In this article we report the Pb contents of petrol and diesel currently manufactured and marketed in the city. Samples of 'Regular' petrol collected in 1999 was found to contain 0.363 g Pb L(-1) (range: 0.335-0.390 g Pb L(-1)), a factor of 5 lower than that marketed prior to 1991. Its concentration in diesel fuel was much lower (0.017 g Pb L(-1)). Based on the available statistical data on the type and volume of vehicular traffic, we assessed that the current lead emission from vehicular traffic into the atmosphere is 391 metric tons a year, which is a factor of 2.7 lower than that estimated for 1989.

Toll Rates and Related Factors on China’s Highways

Toll rates and traffic volumes (or demand) are the two major factors affecting revenue as well as investment strategies on toll roads. Although China has been experiencing dramatic growth in its highway systems during the past 10 years, there has been a lack of understanding in maintaining and operating its toll roads. Since most of the freeways in China are toll roads, it is necessary to establish a methodology for the toll road system based on the characteristics of China’s transportation systems and social economy. A methodology to determine the toll rates for China’s toll road systems is introduced. Factors affecting the toll rate are analyzed, including gross domestic product, total number of vehicles, growth rates of passenger and freight transport, and roadway conditions. The theory of elasticity is applied in a case study to investigate the effect of toll rate on traffic volumes. A critical-volume model is established on the basis of the analyses of various factors such as construction costs, operating costs, expected time of return, and internal rate of return.

HEAVY METALS IN STREET DUST IN BURSA, TURKEY

The trace element contents of street dust samples collected from streets in the Bursa City, Turkey, have been determined by flame-atomic absorption spectrometry after digestion with aqua regia. The mean concentration levels of Pb, Ni, Cd, Zn and Mn were found to be 210, 67, 3.1, 57 and 500 μg/g, respectively. A good correlation between the number of cars or total number of vehicles and the metal contents is found.

Decadal reductions of traffic emissions on a transit route in Austria – results of the Tauerntunnel experiment 1997

Real-world emissions of a traffic fleet on a transit route in Austria were determined in the Tauerntunnel experiment in October 1997. The total number of vehicles and the average speed was nearly the same on both measuring days (465 vehicles 30 min −1 and 76 km h −1 on the workday, 477 and 78 km h −1 on Sunday). The average workday fleet contained 17.6% heavy-duty vehicles (HDV) and the average Sunday fleet 2.8% HDV resulting in up to four times higher emission rates per vehicle per km on the workday than on Sunday for most of the regulated components (CO 2, CO, NO x , SO 2, and particulate matter-PM10). Emission rates of NMVOC accounted for 200 mg vehicle −1 km −1 on both days. The relative contributions of light-duty vehicles (LDV) and HDV to the total emissions indicated that aldehydes, BTEX (benzene, toluene, ethylbenzene, xylenes), and alkanes are mainly produced by LDV, while HDV dominated emissions of CO, NO x , SO 2, and PM10. Emissions of NO x caused by HDV were 16,100 mg vehicle −1 km −1 (as NO 2). Produced by LDV they were much lower at 360 mg vehicle −1 km −1. Comparing the emission rates to the results that were obtained by the 1988 experiment at the same place significant changes in the emission levels of hydrocarbons and CO, which accounted 1997 to only 10% of the levels in 1988, were noticed. However, the decrease of PM has been modest leading to values of 80 and 60% of the levels in 1988 on the workday and on Sunday, respectively. Emission rates of NO x determined on the workday in 1997 were 3130 mg vehicle −1 km −1 and even higher than in 1988 (2630 mg vehicle −1 km −1), presumable due to the increase of the HD-traffic.

Analytical Dynamic Network Loading Problem: Formulation, Solution Algorithms, and Computer Implementations

The dynamic network loading problem is considered. This problem is at the heart of analytical approaches to dynamic traffic assignment models. Given path flow rate and link travel time functions, the dynamic network loading problem consists of determining time-dependent network flow conditions, such as link travel times, total number of vehicles on links, and link inflow and outflow rates. The dynamic network loading problem is formulated as a continuous-time system of nonlinear equations expressing link dynamics, flow conservation, flow propagation, and boundary constraints. A discrete-time version of the continuoustime model is developed to design solution algorithms. Two solution algorithms are developed and implemented efficiently. Techniques are described that were designed to reduce memory usage and computation times of these solution algorithms. Computational results with a realworld traffic network emanating from the Amsterdam A10 beltway, containing 300 nodes, 1,500 paths, 1,000 origin-destination pairs, and 2 h of analysis period indicate that the developed computer implementations can solve the network loading problem in 2 min when a small discretization interval of 3.5 s is used.

Heavy metal pollution in the western part of Peshawar metropolis, north Pakistan

Peshawar is the capital of North-West-Frontier-Province (NWFP) and the largest trade centre in the northwestern part of Pakistan. Due to high rate of urbanisation and the sudden influxes of Afghan refugees in the past two decades, the city has become one of the most polluted ones in the South Central Asia. The increased load of transportation with no or limited expansion of roads, unplanned and uncontrolled industrialisation and poor sanitation have caused the atmosphere unprecedently overburdened with smokes and dusts of all kinds. This paper is a part of a detail study carried out to determine heavy metal concentrations in air dust, soil and sewerage of the Peshawar metropolis.
 In the western part of Peshawar metropolis at 16 chowks (road crossings), air dust samples were collected at nose height and at ground positions in open buckets filled with distilled water for 48 hours. From the same locations, clay/road-mud samples were collected from solidified clay on ground surface. Similarly, soil samples were collected from non-metalled parts at 2 feet depths in subsurface from 10 locations. Correspondingly, sewerage samples were collected from sewerage water and sewerage mud. Vehicular traffic counting was carried out at each chowk for 12 peak hours. At nose height the heavy metal contents showed ppm ranges of: Cr= 0.06-3.2, Co= 0.3-2.4, Ni= 0.17-5.97, Cu= 0.88-8.8, Zn = 0.81-17, Fe = 3-57 and Pb 2-25. The heavy metals concentrations at ground positions were noticed to be higher than at the nose level. The soil samples do not show significant enrichment in heavy metals and are therefore classified as the normal soils. In sewerage water samples the heavy metals concentrations showed ppm ranges of Cr= 0.1-3.81, Co= 0-2, Ni = 0.1 -3, Cu = 0.13-3, Zn = 0.1 - 4.3, Fe = 13 -99 and Pb = 1.81-10. Sewerage mud showed higher concentrations of these metals as compared to sewerage water. A systematic positive variations between the atomic masses of the metals and their concentrations was noticed in air, clay, sewerage water and sewerage mud, indicating that the higher the atomic mass, the higher was the rate of fall/deposition of that particular metal, if available. It was also noticed that compared with water, air is a finer sorting agent for heavy metals.
 At each chowk, both individual metal and the total dust fall showed positive correlation with the total number of vehicles, indicating that the moving vehicular traffic is the major cause of keeping metals­ loaded dust in the air. However, these vehicles may not be considered as the major source of emanating these metals from their exhausts. The study showed that the major sources of heavy metals in the western part of Peshawar metropolis are small metal shops, workshops, construction projects, rusted bridges, fences and vehicles on the roads as well as the damaged sewerage system.

Integrated fire and ambulance siting: A deterministic model

The model presented in this paper is developed for an integrated emergency system in which ambulance and fire service deployment are simultaneously considered. The model extends and blends the Maximal Covering Location Problem (MCLP) for ambulance siting and the Facility Location-Equipment Emplacement Technique (FLEET) for fire service placement. The objective of the new formulation is to maximize and trade-off both ambulance and fire coverage subject to constraints on the total number of vehicles and stations of both types that can be sited. We introduce a new concept in integrated coverage that permits free-standing ambulance stations to be sited in addition to fire stations. Typically, ambulances are located at fire stations and, sometimes, hospitals; that is, eligible sites are driven by prior choices that did not include consideration of ambulance service. Our results, based on three sample problems, suggest that, for a given budget level for facility construction, it may be possible for ambulance coverage to be increased with little or no loss in fire coverage. This condition pertains if ambulance stations are freed of the requirement to be sited only at fire stations.

Steady state results for the transportation system with k-class of vehicles

The transportation system considered in this paper has k-classes of vehicles with finite capacity constraints. The number of vehicles may vary from class to class but the total number of vehicles at the depot (source terminal) is finite. The kth class of vehicles is the reserve class of vehicles and is used only when passenger queue length exceeds to certain limit, Using an iterative method various system performance measures have been obtained.

Highway Delays Resulting From Flow-Stopping Incidents

Modern highways, particularly the freeways of large cities, carry a considerable volume of traffic during certain times of day. Thus if any interruption or retardation of flow occurs, a large reaction in the shape of a monumental and time-consuming traffic jam soon appears. For example, when an accident or mechanical breakdown gives rise to a severe flow restriction or stoppage, many other vehicles may be quickly halted, and remain stopped until the impediment is cleared away. In addition, the flow of traffic may be slowed considerably even after the original stoppage is removed owing to the existence of a queue. Consequently, vehicles that arrive long after the original restriction is removed experience prolonged, and sometimes seemingly inexplicable, delay. Our purpose is to develop a probability model for the situation described, with the aim of estimating the consequence of a temporary flow restriction. Various measures of (in)effectiveness are worth considering. We consider primarily the total vehicle-hours waited while the jam dissipates; the latter may roughly measure total social cost. The total number of vehicles involved in the jam is also of interest, as are other figures of merit.