Writing in a forthcoming issue of the Inderscience publication the International Journal of Logistics Systems and Management, researchers suggest a new approach to cutting journey times and so reducing pollution and speeding up deliveries for couriers everywhere.
According to Chandra Sunil Kumar and T.T. Narendran of the Department of Management Studies, at IIT-Madras, in Chennai, India, the Travelling Salesman Problem, or to give it its modern name the Vehicle Routing Problem (VRP), is one of the biggest headaches for companies running delivery and pickup services - how to ensure the route taken by the couriers is not only as short as possible and so uses the least fuel but also ensures that all drop-offs and pick-ups are made in a timely manner. The efficiency of services involving express couriers, dial-a-ride systems, and partial-truck-load carriers might all be improved.
Narendran and colleagues have devised a computer model to investigate how companies might map out the optimum routes for their couriers.
In their model the researchers consider a single vehicle operating within a region. Each day, there are calls from customers, packages to deliver, and others to collect and deliver elsewhere. Static customer requests are those that are known in advance, while dynamic requests arise as the day progresses. The vehicle starts from the depot, moves to serve static customers according to a schedule of advance requests. As the day progresses, new requests come in and the dispatcher has to re-route to fulfil these new requests while minimising the total distance travelled in accommodating advance bookings.
The vehicle then follows the latest determined route until a new dynamic request arrives. At that time, the vehicle is between the start and finish of the original plan. Now the plan has to add a pickup and delivery point into the unexecuted part of the plan so that the additional distance to be travelled is minimised. At this juncture, the computer model inserts a heuristic - a rule of thumb. In one method, the customer's new request is positioned appropriately between two of the places to be visited as per the original plan. In the second approach, the entire sector remaining to be served is reframed with the inclusion of the new request; this part of the problem is solved afresh using an optimization approach.
The team has carried out tests of the model computationally and found that the distance travelled by the vehicle increases with increasing numbers of new requests. However, the heuristics can work in real-time and every time a new request arises, they can process the information and re-route the vehicle to keep the total distance as low as possible.
The team points out that their system will not only help courier companies but could be used equally well by dial-a-ride services, which fill the gap between public transport and taxi cabs, fast food and groceries home deliveries, emergency service responses, including fire, police, and ambulance, repair services, and perhaps even parcel and mail delivery services.
Jim Corlett | alfa
Study sets new distance record for medical drone transport
13.09.2017 | Johns Hopkins Medicine
Researchers 'count cars' -- literally -- to find a better way to control heavy traffic
10.08.2017 | Florida Atlantic University
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.
In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...
Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale
Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy