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Time–space conflicts are one of the most common issues facing construction practices, impacting safety and productivity in several negative ways at construction sites. Therefore, implementing and developing methods to reduce the frequency of such conflicts occurring in activity workspaces can effectively enhance project performance. Space is usually a constrained resource in construction project sites; therefore, in this project, we propose an approach as a method of time–space conflict management in construction project sites. The method implements Informed Rapidly Exploring Random Tree-Star (Informed-RRT*) path planning, Discrete Event Simulation (DES), and geometry to automatically detect and resolve time–space conflicts in construction projects. To evaluate the method's capabilities, it is tested on a case study of an earthwork operation, including the loading, hauling, dumping, and return phases. Finally, our method finds the shortest travel path and duration for each hauling truck between two given starting and end points in each phase without colliding with static obstacles (randomly placed in the site), intersection points of the trucks' path, the start and stop time for the truck serving higher-priority construction activities, and the total duration of each truck's earthwork operation. [ABSTRACT FROM AUTHOR]

The decisions managing all modes of transportation are currently based on the traffic rate and travel time. However, other factors such as Green House Gas (GHG) emissions, the sustainability index, fuel consumption, and travel costs are not considered. Therefore, more comprehensive methods need to be implemented to improve transportation systems and support users' decision making in their daily commute. This paper addresses current challenges by utilizing data analytics derived from our proposed mobile application. The proposed application quantifies various factors of each transportation mode including but not limited to the cost, trip duration, fuel consumption, and Carbon Dioxide (CO2) emissions. All calculated travel costs are based on the real-time gas prices and toll fees. The users are also able to navigate to their destination and update the total travel costs in real-time. The emissions data per trip basis are aggregated to provide analytics of emissions usage. The traffic data is collected for the Southern California region and the effectiveness of the application is evaluated by twenty participants from California State University, Long Beach. The results demonstrate the application's impacts on users' decision-making and the propriety of the factors used in route selection. The proposed application can foster urban planning and operations vis-à-vis daily commutes, and as a result improve the citizens' quality of life in various aspects. [ABSTRACT FROM AUTHOR]

Any change in the geometric configuration of the existing road affects other dependent elements such as travel time, fuel consumption, and existing pavement. This paper quantifies these effects and finds an optimum geometric configuration. Three separate models are developed in this research: (1) the travel time model which predicts vehicles flow speed on the specified geometric condition, traffic composure, and evaluates the imposed costs to the road users; (2) the fuel consumption model, which estimates needed propulsive force and anticipated fuel for vehicles passing through the road; and (3) the pavement rehabilitation cost model considering two main constraints of existing pavement condition and project line elevation. The developed pavement rehabilitation model proposes the best solution for pavement rehabilitation practice and computes associated costs. Particle Swarm Optimization (PSO) is used to find the optimum solution in a minimization problem search space. The proposed model is applied to a real-world case study. Results show that there is an extremely less tendency for change, even with the existence of adverse geometric conditions, when there is a relatively good pavement condition. In the case of deteriorated pavement conditions, economic justification for geometric modification is required. [ABSTRACT FROM AUTHOR]