Probabilistic Dynamic Programming Applied to Transportation Network Optimization (original) (raw)
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Advances in Intelligent Systems and Computing
Finding the employee pickup location plan is a hard work for transportation companies because it is a manual task that takes hours of work with the possibility of error. In this context, we propose an adaptive decision system that allows transport companies to find the optimal path. The proposed system is based on an optimization process that maximizes the fill rate and minimizes pickup time. In this article, we present the process of time optimization and the path for personnel transport. The process generates a plan for the points to be visited and the number to be transported for each vehicle. The proposed process consists of four stages: the first one allows to model the real situation in directed graph; the nodes are the pickup location and the arcs are the roads. The second step is to represent the graph in the form of a square matrix of order (n * n) knowing that n is the number of pickup points. The third step generates all possible paths with the number of each trip. Based on the results of the third step, we assign vehicles to each journey based on type and capacity, starting with the path that has the most manpower in order to transport the maximum number of personnel. After having specified the points to be visited, we use the Dijiksra algorithm to find the optimal route to follow taking into account the traffic jam.
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Journal of Information and Data Management - JIDM, 2018
The increase in urban population, together with the expansion of cities, has motivated the study of improvements for dynamics aspects of daily urban life. An important portion of these dynamic aspects is related to the population’s routine activities, like commuting using public transportation. This work proposes two meta-heuristics and one integer programming modeling to analyze the location of bus stops and propose new pick-up and drop-off locations in order to avoid long walks to take the bus. A real dataset of the road network was integrated to the location of bus stops in the city of Belo Horizonte. Computing approaches were proposed to optimize the location of bus stops in a scalable way. Experimental results show that many new bus stops are required to improve the quality of the service rendered to the population.
Sretechjournal Publications, 2018
In this case study, considered the vehicle routing problem with pickup and delivery which is a generalization of the capacitated vehicle routing problem (CVRP). The vehicle routing problem with pickup and delivery (VRPPD) arises whenever pickup demand and delivery demand is to be satisfied by the same vehicle. The problem is encountered in many real life situations. In this paper problem arises from the distribution of beverages and collection of recyclable containers. It can be modeled as a variant of the vehicle routing problem with a heterogeneous vehicle fleet, capacity and volume constraints, and an objective function combining routing distance or minimizing the total travel distance to serve customers located to different locations. Three construction heuristics and an improvement procedure are developed for the problem and designing a set of routes with minimum cost to serve a delivery of beverages and a collection of recyclable material with a fleet of vehicles. The aim of this paper is to develop a vehicle routing Problem (VRP) model that addresses simultaneous pickup and delivery in the beverage distribution. To this effect, a mathematical model is adopted and fitted with real data collected from MOHA Soft drinks Summit Plant located in Ethiopia, and solved using Clark-Wright saving algorithm. The form-to-distance is computed from the data collected from Google Earth and the customer’s data from the MOHA. The findings of the study show that the model is feasible and showed an improvement as compared to the current performances of the plant with respect to product distribution and collection and the total distance covered is minimized about 27.79%. The average performances of the model show that on average 5 routes are required to serve customers’ demands.
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Influence of Unscheduled Random Public Bus Stops on Transit Travel Time
Journal of Traffic and Logistics Engineering, 2013
Transit Travel time can affect to a large extent the service reliability, operating cost, and system efficiency. This research paper aims to study the negative impact of the unscheduled random public bus stops on travel time for a particular bus route in Cairo, Egypt. These unscheduled stops became a usual behavior for Cairo Public buses, which affects more than four and a half million daily users of this transportation service inside Cairo. In this study, a comprehensive research plan was designed to collect the data concerning the bus behavior along a selected bus route, using GPS data logger. The data collection included time, location, speed, unscheduled stops, and scheduled stops. The collected data was then used to develop a trip time model. The developed model revealed the delay time due to the unscheduled bus stops and the scheduled bus stops. The analysis of the data also showed that passengers rely much more on the unscheduled random bus stops than the scheduled bus stops. The study concluded that minimizing the unscheduled bus stops will decrease the trip time, and so improve the service reliability to a large degree. Index Terms-Travel time, unscheduled random public bus stops, GPS data logger, trip time model, service reliability. 20
Optimization of New Pick-up and Drop-off Points for Public Transportation
The expansion of cities, together with the advance of technological resources, has motivated the study of improvements for metropolitan dynamics. Among these improvements are those aiming to facilitate and to speed up the population's routine activities. This work proposes and compares two methods to optimize the location of new pickup and drop-off points in order to avoid long walks to get to a bus stop. Real datasets of the road network and bus stops in the city of Belo Horizonte were used. Results indicate the effort required by the city's transit system to provide transit pickup and drop-off points in a reasonable quantity and location, in order to improve the quality of the service rendered to the population.