Historical manifest data from a parcel carrier undertaking 'next-day' (i.e. non-express) deliveries in an area of central London (mainly EC2 postcode district) were used to quantify the potential benefits of switching from the current van-based deliveries to one where porters or cycle couriers are used for the last-mile delivery, working from set drop-off points.The results suggested that over the business-as-usual case for the area of London studied, the carrier could reduce CO2 emissions by 45% (9500kg/year) and NOx emissions by 33% (7.64kg/year). Annual driving distance could be reduced by 78% (48,100km) and the amount of time spent stationary at the curbside by 45% (2558 hours/year). Scaling up the modelled emissions savings to London's Central Activities Zone, an area approximately 10 times bigger than the modelled case study area and with estimated total annual parcel delivery distance of 15 million km, could see annual emissions savings in the region of 2 million kgCO2 and 1633kgNOx if all carriers utilised porters or cycle couriers. Overall cost savings to the carrier were estimated to be in the range 34%-39%. Some practical operating challenges are identified including sorting and packing of items, parcel handover arrangements, how to deal with failed deliveries, and how to incorporate express items.
One approach to improving antibiotic stewardship in primary care may be to support all General Practitioners (GPs) to have access to point of care C-Reactive Protein tests to guide their prescribing decisions in patients presenting with symptoms of lower respiratory tract infection. However, to date there has been no work to understand how clinical commissioning groups might approach the practicalities of system-wide implementation. We aimed to develop an accessible service delivery modelling tool that, based on open data, could generate a layout of the geographical distribution of point of care facilities that minimised the cost and travel distance for patients across a given region. We considered different implementation models where point of care tests were placed at either GP surgeries, pharmacies or both. We analysed the trade-offs between cost and travel found by running the model under different configurations and analysing the model results in four regions of England (two urban, two rural). Our model suggests that even under assumptions of short travel distances for patients (e.g. under 500m), it is possible to achieve a meaningful reduction in the number of necessary point of care testing facilities to serve a region by referring some patients to be tested at nearby GP surgeries or pharmacies. In our test cases pharmacy-led implementation models resulted in some patients having to travel long distances to obtain a test, beyond the desired travel limits. These results indicate that an efficient implementation strategy for point of care tests over a geographic region, potentially building on primary care networks, might lead to significant cost reduction in equipment and associated personnel training, maintenance and quality control costs; as well as achieving fair access to testing facilities.
Inspired by actual parcel delivery operations in London, this paper describes a two-echelon distribution system that combines the use of driving and walking as part of last-mile deliveries in urban areas for a single driver. The paper presents an optimisation model that explicitly treats and integrates the driving and walking elements, and describes a branch-and-cut algorithm that uses new valid inequalities specifically tailored for the problem at hand. Computational results based on real instances obtained from a courier operating in London are presented to show the performance of the algorithm.
Packing Three-Dimensional Irregular Objects Because of its many applications in practice, the cutting and packing literature is extensive and well established. It is mostly concerned with problems in one and two dimensions or with problems where some regularity of the pieces is assumed (e.g., packing boxes). However, the rise of applications in the realm of three-dimensional printing and additive manufacturing has created a demand for efficient packing of three-dimensional irregular objects. In “Voxel-Based Solution Approaches to the Three-Dimensional Irregular Packing Problem,” Lamas-Fernandez, Martinez-Sykora, and Bennell propose a series of tools to tackle this problem using voxels. These include geometric tools, a mathematical model, local search neighborhoods, and details on implementation of metaheuristic algorithms. These tools are tested extensively, and computational results provided show their effectiveness compared with state-of-the-art literature.
Parcel logistics in urban areas are characterized by many carriers undertaking similar activity patterns at the same times of day. Using substantial carrier manifest datasets, this paper demonstrates advantages from rival carriers collaborating using a “carrier’s carrier” operating model for their last-mile parcel logistics operations. Under these circumstances, a single carrier undertakes all the deliveries within a defined area on behalf of the carriers instead of them working independently. Modelling the daily delivery activity of five parcel carriers working over a 3.7 km2 area of central London, comprising around 3000 items being delivered to around 900 delivery locations, and consolidating their activity through a single carrier suggested that time, distance and associated vehicle emissions savings of around 60% could be achieved over the current business-as-usual operation. This equated to a reduction in the number of delivery vans and drivers needed from 33 to 13, with annual savings of 39,425 h, 176,324 km driven, 52,721 kg CO2 and 56.4 kg NOx. Reliance on vans and associated vehicle emissions could be reduced further by using cargo cycles alongside vans for the last-mile delivery, with estimated annual emissions savings increasing to 72,572 kg CO2 and 77.7 kg NOx. The results indicated that consolidation of items for delivery in this way would be especially beneficial to business-to-consumer (B2C) carriers whose parcel profiles comprise relatively small and light items. One of the key barriers to the wider take up of such services by individual carriers is the loss of individual brand identity that can result from operating through a carrier’s carrier.
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