A column-generation matheuristic approach for optimizing first-mile ridesharing services with publicly- and privately-owned autonomous vehicles

The burden of first-mile connection to public transit stations is a key barrier that discourages riders from taking public transportation. Public transit agencies typically operate a modest fleet of vehicles to provide first-mile services due to the high operating costs, thus failing to adequately meet the first-mile travel demands,...

Mode I fracture behavior of glass fiber composite-steel bonded interface: Experiments and CZM

Debonding is characterized as the governing failure mode in the innovative wrapped composite joints made with glass fiber composite material wrapped around steel hollow sections without welding. The prerequisite for predicting debonding failure of wrapped composite joints is to obtain fracture behavior of the composite-steel bonded interface....

The flexible airport bus and last-mile ride-sharing problem: Math-heuristic and metaheuristic approaches

Airport buses play a crucial role in addressing the last-mile problem of air travel, especially in cities and countries lacking inner-city rail transit systems. Nevertheless, airport buses are currently witnessing a decline in ridership due to drawbacks such as long departure intervals, inflexible stops, and considerable distances between...

Debonding Resistance of CHS Wrapped Composite X-Joints

Influence of steel yielding and resin toughness on debonding of wrapped composite joints

The concept of an innovative bonded joining technology where welding is not required is presented as an alternative to traditional welded connection for steel circular hollow section (CHS). Wrapped composite joints have potential to greatly improve fatigue endurance when applied in multi-membered truss structures, e.g. offshore jackets for...

Optimizing first-mile ridesharing services to intercity transit hubs

Travel to intercity transportation hubs, such as railway stations and airports, can be the most troublesome and inefficient part of the entire air/railway travel journey, as travelers often carry large luggage and have stringent arrival time requirements. Taking public transportation, such as metro and bus services, is inconvenient to carry...

Single-Molecule Structure and Topology of Kinetoplast DNA Networks

Kinetoplast DNA (kDNA) is a two-dimensional Olympic-ring-like network of mutually linked DNA minicircles found in certain parasites called trypanosomes. Understanding the self-assembly and replication of this structure are not only major open questions in biology but can also inform the design of synthetic topological materials. Here, we...

DIC-based monitoring on debonding crack propagation in wrapped composite joints

Wrapped composite joint is an innovative technique which connects steel hollow sections through bonding such that the fatigue performance is improved compared to welded joint. In this paper, a DIC-based method of monitoring surface strains is proposed to quantify the debonding crack propagation within the composite wrap layers during high cycle...

Failure modes of bonded wrapped composite joints for steel circular hollow sections in ultimate load experiments

The concept of an innovative bonded joining technology where welding is not required is presented as an alternative to traditional welded connection for steel circular hollow section (CHS). Wrapped composite joints have potential to greatly improve fatigue endurance when applied in multi-membered truss structures, e.g. offshore jackets for...

Combined DIC and FEA method for analysing debonding crack propagation in fatigue experiments on wrapped composite joints

Wrapped composite joint is a novel joining technology which connects steel hollow sections through bonding, completely avoiding the welding in the load transferring mechanism. Fatigue performance of wrapped joints has been experimentally shown to be superior over their welded counterparts. Aiming to enable development of prediction methods...

Mesoscale modelling of optical turbulence in the atmosphere: The need for ultrahigh vertical grid resolution

The high-fidelity modelling of optical turbulence is critical to the design and operation of a new class of emerging highly sophisticated astronomical telescopes and adaptive optics instrumentation. In this study, we perform retrospective simulations of optical turbulence over the Hawaiian islands using a mesoscale model. The simulated...