Air quality, regarded a main infrastructure element in urban transportation system, is considered as a major criterion for human settlement. Therefore transport emitted air pollution appears related to the establishment of urban landuse in proportion to urban transportation network. Increasing demand for residential areas, along with this development of cities, has given rise to some environmental issues (Bell and Blake, 2000; Ranjan, 2001). More than half of the world's population lives in urban areas (Colesca S., 2009), therefore increasing urban land-uses resulted in several impacts on various fields such as air quality, accessibility and land use. Air quality has been considered as one of the major environmental elements by many urban planners (Colvile et al. 2000; Nicolas et al. 2005). Therefore, there is a need to look into urban transportation planning together with landuse development.
With respect to above note, paper presents development of a mathematical model to find suitable locations for landuses and urban transportation network for the urban transportation system of Petaling Jaya Municipal Council (MPPJ). The model essentially investigated the best air quality for residential area. It was based on the optimum distance from residential zones to urban networks as main element avoiding transport emitted air pollution.
Petaling Jaya Municipal Council (MPPJ), a developing city in Malaysia, was chosen as study area, Its based on choices of environmental factors such as: several routes to access to important public facilities, High transportation activities, Efforts to maintain its "garden city" concept, Efforts to establish well-developed infrastructures and excellent investment opportunities.
2. RESEARCH APPROACH
The works undertaken includes several statistical and mathematical analysis of urban planning, focusing on land use and air quality using Geographic Information System (GIS) as visualization platform. Distance of residential land use from urban transportation network is modeled based on determining factors of Carbon Monoxide (CO) emission from vehicles movement. This emission is useful for modeling suitable locations of residential land use in urban areas. The determination of factors is based on their analyzing individual role in CO emission. Relevant factors such as plume rise of CO, average atmospheric temperature and pressure, stack exiting velocity, estimated stack diameter, average wind speed and traffic volume are determined based on historical data (Highway Planning Unit, 2004) and standard definition of road types. Mathematical analysis methods, used to determine quantitative role of factors in the model, include programming by software of Excel and power function analyzing.
The air quality expected with respect to CO distribution is modeled using the basic theory of Primary Standard of CO Pollutant in 8 hours averaging time (WHO, 2000), which shows that the threshold of air pollution for human health in Malaysia is considered equal to 10 mg/[m.sup.3].
The model development method is based on the maximum ground level concentration of CO, considering the spread of a plume in vertical and horizontal directions, which is assumed to occur by simple diffusion along the direction of the mean wind. CO like other pollutants accumulates based on stability time, independently or in conjunction with atmospheric temperature and pressure, wind speed, curb length, or area. Curb length of CO, as indicator of suitable distance to locate residential zones, can be a function of plume rise of CO, average atmospheric temperature and pressure, stack exiting velocity, estimated stack diameter, average wind speed and traffic volume. This function can be restructured for the study area (MPPJ) to plan future urban development and improvement.
2.1 MATHEMATICAL MODELING TRAJECTORY
The base of mathematical trajectory is combination of several relative formulas and models to calibrate a new model in relation to statement problem. …