Emergency vehicle lane pre-clearing: From microscopic cooperation to routing decision making

Emergency vehicles (EVs) play a crucial role in providing timely help for the general public in saving lives and avoiding property loss. However, very few efforts have been made for EV prioritization on normal road segments, such as the road section between intersections or highways between ramps. In this paper, we propose an EV lane pre-clearing strategy to prioritize EVs on such roads through cooperative driving with surrounding connected vehicles (CVs). The cooperative driving problem is formulated as a mixed-integer nonlinear programming (MINP) problem aiming at (i) guaranteeing the desired speed of EVs, and (ii) minimizing the disturbances on CVs. To tackle this NP-hard MINP problem, we formulate the model in a bi-level optimization manner to address these two objectives, respectively. In the lower-level problem, CVs in front of the emergency vehicle will be divided into several blocks. For each block, we developed an EV sorting algorithm to design optimal merging trajectories for CVs. With resultant sorting trajectories, a constrained optimization problem is solved in the upper-level to determine the initiation time/distance to conduct the sorting trajectories. Case studies show that with the proposed algorithm, emergency vehicles are able to drive at a desired speed while minimizing disturbances on normal traffic flows. We further reveal a linear relationship between the optimal solution and road density, which could help to improve EV routing decision makings when high-resolution data is not available

Modelagem matemática para localização de bases de despacho de veículos de resgate: um estudo de caso no município do Rio de Janeiro

The Emergency Medical Services are considered critical elements of modern health services, mainly to ensure that the level of service is appropriate for the population of the region that serve, as it depends on the service the worsening or not of the victim’s health condition. We applied Facility Location Problems, in this context, to indicate strategic points to the location of rescue vehicles dispatching bases attending emergency calls. In the city of Rio de Janeiro, this type of service is the responsibility of the Military Fire Department of the State of Rio de Janeiro, which has units distributed throughout the territory, where the rescue vehicles are dispatched. Therefore, the objective of this work is to propose a mathematical modeling to support the planning of the location of rescue vehicles dispatching bases, focusing on the maximization of the population coverage and different types of occurrences recorded and the minimization of the number of dispatch bases opened and the distance between the dispatch bases and the demand points. Bibliographic and documentary researches were carried out with the purpose of understanding the main characteristics of the location / allocation of ambulance dispatch bases and the main mathematical models of facilities location. Tests were implemented for 11 scenarios with variations in the number of bases and vehicles used which, with the help of georeferencing tools, allowed us to evaluate the coverage and service time for each base in each scenario.Os Serviços Médicos de Emergência são considerados elementos críticos dos sistemas de saúde, pois necessitam assegurar que seu nível de serviço esteja adequado à população a qual serve, uma vez que dele depende o agravamento ou não do estado de saúde da vítima. Neste contexto, os Problemas de Localização de Facilidades vêm sendo aplicados com a finalidade de indicar pontos estratégicos para a localização de bases de veículos que realizam o atendimento às chamadas de emergência. No município do Rio de Janeiro este tipo de serviço é de responsabilidade do Corpo de Bombeiros Militar, que possui unidades distribuídas ao longo do território, de onde são despachados os veículos de resgate. Sendo assim, o objetivo deste trabalho é propor uma modelagem matemática para subsidiar o planejamento da localização de bases de despacho de veículos de resgate, que leve em conta a maximização da população coberta e dos diferentes tipos de ocorrência registrados e a minimização do número de bases de despacho abertas e da distância entre a base de despacho e o ponto de demanda. Pesquisas bibliográficas e documentais foram realizadas com o intuito de compreender as principais características da localização/alocação de bases de despacho de ambulâncias e dos principais modelos matemáticos de localização de facilidades. Foram implementados testes para 11 cenários, com variações no número de bases e de veículos utilizados que, com o auxílio de ferramentas de georreferenciamento, possibilitaram a análise da cobertura e do tempo de atendimento para cada base, em cada cenário