Institutt for regnskap, revisjon og foretaks­økonomi

Journal of Banking & Finance 190 Doi: https://doi.org/10.1016/j.jbankfin.2026.107765

Waste Management Bulletin 4(3) s. 100328-100328 Doi: https://doi.org/10.1016/j.wmb.2026.100328

Optical sorting systems offer convenient municipal waste management but face persistent challenges with material purity and cross-contamination. In Oslo, these long-standing issues have been exacerbated by recent policy incentives that unintentionally discouraged proper sorting, and stricter regulatory targets are now prompting a re-evaluation of source separation. Using Oslo’s complete road network and operational data, we model three curbside food-waste collection strategies through arc-routing optimization: the current commingled baseline, separate collection with dedicated single-compartment fleets (residual stream collected weekly or bi-weekly), and co-collection with multi-compartment vehicles The logistical impact depends strongly on the chosen strategy. Decoupling streams into separate fleets introduces significant route redundancy: weekly separate collection adds about 17% driving distance at current sorting levels, and switching the residual stream to bi-weekly roughly halves this penalty without closing it. Co-collection minimizes this penalty by preserving route density, with transport requirements approaching the commingled baseline as the compartment split better matches the waste-generation ratio, falling within 3% under close matching. However, transport minimization comes at the cost of operational adaptability. Multi-compartment vehicles impose rigidities on collection frequencies and offloading infrastructure, and their efficiency is fragile: it requires precise alignment between compartment configuration and waste generation, a target that shifts as sorting compliance evolves. The dedicated-fleet penalty is structural: each fleet traverses the network independently, and reducing the residual collection frequency narrows but does not close the gap. Collection strategy, infrastructure placement, and the policy levers shaping compliance together determine the transportation outcome and should be planned jointly rather than separately.

Journal of Accounting, Auditing and Finance Doi: https://doi.org/10.1177/0148558X261473714

Operations Research, Data Analytics and Logistics (ORDAL) 47 s. 200510-200510 Doi: https://doi.org/10.1016/j.ordal.2026.200510

Every year, tens of thousands of patients die world-wide because of infections associated with the health system. One source of hospital-acquired infections which reportedly have reached prevalence levels of 7%–10%, are poor hygiene measures. These can be addressed, among others, by a reliable hospital cleaning workforce, responsive to hospital requirements and safety standards. In this paper, we address the problem of hospital-wide scheduling of cleaners handling routine and ad-hoc cleaning demand. Demand which can be subject to variation in arrivals and duration accrues in locations such as emergency departments, operating theatres, and wards. On the supply-side, cleaners have different working regulations which means that breaks and a maximum work duration must be considered. To model the problem, we develop a hybrid simulation model which captures these features and enables us to evaluate the current workforce schedule from a collaborating European hospital using a variety of performance metrics and levels of detail. Using a mixed-integer linear programming approach, we generate alternative schedules that indicate substantial improvements as compared to current planning. This provides a more reliable and safer environment for patients and staff.

European Journal of Operational Research Doi: https://doi.org/10.1016/j.ejor.2026.06.001