ABSTRACT UML is widely used as an industry standard for modeling any system. In this paper will be dealing with simple UML diagrams and show that low it can be transformed into process algebra models specially designated to model urban traffic systems. The model capture functionality at the level of mesoscopic as well as microscopic level and it is merged with process algebra's producer consumer theory. The model is also formalized using Process algebra equations. This paper focuses on complex situational activity diagrams enhancing the expressivity by refining at the abstraction levels. Performance requirement is annotated by the UML profile for schedulability performance and time. INTRODUCTION There are number of information processing methodologies (Rao, Teran, & Savard, 2004) used in modeling Urban Traffic flow but unfortunately they are not able to model the Traffic flow completely. We would like to suggest a methodology by using UML (Buchholz, 2000) which will help in easily building Macroscopic, mesoscopic and microscopic models (Aalast & Van Hee, 2002; Darbari, 2003). The modeling methodology which we will be following can be divided into two sub classifications. Decision Model and Physical model. The decision model contains various functionalities and Control Algorithms (Galup, Dattero, & Quan, 2004; Jitpaiboon & Kalaian, 2005) and Physical model contains operational details. [FIGURE 1 OMITTED] GENERATION OF DECISION MODEL USING UML Decision Models are based on average signal timings. They are particularly useful for signal system timing design software because they provide efficient procedures for formulating objective functions used in optimization logic. In the post decade, many decision models have incorporated more details to account for actuated signals and coordination between them. [FIGURE 2 OMITTED] We can have the basic class diagram (Tari, 2000) being converted into producer consumer methodology. [FIGURE 3 OMITTED] Converting the Class diagram in Figure 2 in Producer Consumer methodology we can have. [FIGURE 4 OMITTED] We can generate collaboration/ State diagram for UTS in Producer consumer mode. [FIGURE 5 OMITTED] The basic diagram for producer/Consumer of the combined collaboration/State Diagram. [FIGURE 6 OMITTED] GENERATING A PROCESS ALGEBRA MODEL OF UTS Generation of a process algebra Model (Hilston,1997) from the UML (Ashley, Meehan, & Carr,2005) model concentrates on the combined collaboration and state chart diagram shown in Figure 6. The transition from producer to blocked requires the completion of the produce action which let us twice t1. In PEPA (Gilmore, 2002) terms this translates to a rate of 2/t1. The transition from blocked to producer requires completion of the passive action add. Communication way def (Main Road, 1/t1). Blocked def (add, T). Communication way Traffic flow def (Free lanes 1/t2). Halted Halted def (take T). Traffic Flow. The Buffer is a simple counting process, which will not allow a take action if it has zero substances and will not allow an add if it has all the free sub lanes with it. The decision to define rates for add and take only in the buffer is arbitrary and in a real example they might be defined in the other processes as well or instead. Main Road Blocked def (add 1/3) Sublane 1 Sub lane and Overflow def (add 1/3). Sublane + (take 1/4). Main Road Blocked. Sublane 2 Overflow def (add 1/3). All Sublane + (take , 1/4) Sublane 1. …