3 research outputs found

    The Conditional Connectivity of Graphs

    Get PDF
    图的连通性是图论的一个基本研究课题,它与网络的可靠性(容错性)密切相关.图的经典的连通性是用连通度和 边连通度来度量的.图的连通度(边连通度)就是使图不连通所要删除的最小的点(边)数,显然它反映了相应的网络的容错性. 在通信网络的可靠性的进一步研究中,人们需要了解两个具有相同的连通度或边连通度的图,哪个可靠性更高? 为了深入研究网络的可靠性或容错性,人们提出了许多条件连通性的概念. Harary在1983年引入条件连通度的概念\cite{2}.设图G=(VE)G=(V,E)PP是图的某种性质,S\subseteqV(G).GG的条件连通度 κ(G:P)\kappa(G:P)=min...The connectivity of graph is an element topic in the research of graph theory, it is closely related to the network reliability (fault tolerance). The classical connectivity concept of graph is connectivity and edge connectivity. Connectivity (edge connectivity) is the minimum number of vertices (edges) whose deletion makes the graph disconnected. Obviously, they reflect the corresponding net...学位:理学博士院系专业:数学科学学院数学与应用数学系_应用数学学号:1912008015045

    Fuelling the zero-emissions road freight of the future: routing of mobile fuellers

    Get PDF
    The future of zero-emissions road freight is closely tied to the sufficient availability of new and clean fuel options such as electricity and Hydrogen. In goods distribution using Electric Commercial Vehicles (ECVs) and Hydrogen Fuel Cell Vehicles (HFCVs) a major challenge in the transition period would pertain to their limited autonomy and scarce and unevenly distributed refuelling stations. One viable solution to facilitate and speed up the adoption of ECVs/HFCVs by logistics, however, is to get the fuel to the point where it is needed (instead of diverting the route of delivery vehicles to refuelling stations) using "Mobile Fuellers (MFs)". These are mobile battery swapping/recharging vans or mobile Hydrogen fuellers that can travel to a running ECV/HFCV to provide the fuel they require to complete their delivery routes at a rendezvous time and space. In this presentation, new vehicle routing models will be presented for a third party company that provides MF services. In the proposed problem variant, the MF provider company receives routing plans of multiple customer companies and has to design routes for a fleet of capacitated MFs that have to synchronise their routes with the running vehicles to deliver the required amount of fuel on-the-fly. This presentation will discuss and compare several mathematical models based on different business models and collaborative logistics scenarios
    corecore