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PurposeLast-mile delivery is associated with a negative environmental impact and high costs. The purpose of this paper is to develop an approach to designing stationary parcel locker (SPL) networks while minimizing both CO2 equivalent (CO2e) emissions and costs during delivery and pick-up.Design/methodology/approachThis study uses a multinomial logit model to evaluate recipients' willingness to use SPLs based on their availability at home and travel distance. To determine optimal SPL locations, this study formulates a mixed-integer linear programming model.FindingsThe empirical study of different regional clusters reveals that optimal SPL locations can generate cost savings of up to 11.0%. SPLs have a positive impact on total CO2e emission savings in urban areas (i.e. up to 2.5%), but give rise to additional emissions (i.e. 4.6%) in less populated areas due to longer travel distances during the pick-up process.Originality/valueThis paper optimizes SPL locations and the ecological effect of SPLs by minimizing emissions and costs simultaneously. Furthermore, it extends existing discrete choice models by also including recipients' availability at home, increasing the accuracy of recipients' preferences. So far, the effect of SPLs has been studied for metropolitan areas only. A global logistics service provider shared a real dataset which allows us to study seven different regional clusters ranging from rural areas to large cities. Thus, this study contributes to the field of sustainable urban logistics.

We analyze the option to breach a leasing contract when replacing a fleet of ICVs (internal combustion engine vehicles) and EVs (electric vehicles) subject to cost uncertainty. We derive the optimal policy for technology choice and breaching ICV contracts. The decision to breach is shown to offer both cost savings resulting from reduced ICV operating costs and preemptive acquisition, but incurs additional costs arising from the need to compensate for breached vehicles and in the form of opportunity costs. We also demonstrate that the effects of breaching a leasing contract have a ripple effect across the decision horizon, thus amplifying the impact of a single breach. A numerical study based on data from La Poste, the French postal service, shows that breaching a leasing contract in this context offers measurable cost benefits.

ABSTRACTThis article considers the optimal pricing of full‐service (FS) repair contracts by taking into account learning and maintenance efficiency effects, competition from service , and asymmetric information. We analyze on‐call service (OS) and FS contracts in a market where customers exhibit heterogeneous risk aversion. While the customers minimize their disutility over the equipment lifetime, the service provider maximizes expected profits arising from the portfolio of OS and FS contracts. We show that the optimal FS price depends inter alia on the customer's prior cost experience and on OS repair and maintenance costs. The optimal FS price is shown to increase as fewer OS customers are lost to competition, whereas improved repair learning enabled by FS reduces the optimal price. A numerical study based on data from a manufacturer of forklifts highlights the importance of learning in maintenance operations, which constitutes the key benefit of FS contracts; 81% of the customers select the FS option and are willing to pay an insurance premium of around 1.5% of total OS cost against volatility of repair costs.

PurposeThe e-commerce boom presents new challenges for last-mile delivery (LMD), which may be mitigated by new delivery technologies. This paper evaluates the impact of mobile parcel lockers (MPL) on costs and CO2 equivalent (CO2e) emissions in existing LMD networks, which include home delivery and shipments to stationary parcel lockers.Design/methodology/approachTo describe customers' preferences, we design a multinomial logit model based on recipients' travel distance to pick-up locations and availability at home. Based on route cost estimation, we define the operating costs for MPLs. We devise a mathematical model with binary decision variables to optimize the location of MPLs.Findings Our study demonstrates that integrating MPLs leads to additional cost savings of 8.7% and extra CO2e emissions savings of up to 5.4%. Our analysis of several regional clusters suggests that MPLs yield benefits in highly populous cities but may result in additional emissions in more rural areas where recipients drive longer distances to pick-ups.Originality/valueThis paper designs a suitable operating model for MPLs and demonstrates environmental and economic savings. Moreover, it adds recipients' availability at home to receive parcels improving the accuracy of stochastic demand. In addition, MPLs are evaluated in the context of several regional clusters ranging from large cities to rural areas. Thus, we provide managerial guidance to logistics service providers how and where to deploy MPLs.

Nowadays, global economic production is organized around a complex system of highly interdependent supply chains that are currently enormously disrupted due to COVID 19. What would happen if a fast-growing risk could pose a more significant threat to our supply chains? Are our supply chains resilient to climate change? Even though governments, businesses, and climate change organizations in developed countries are forced to work together trying to mitigate and adapt to this fast-moving phenomenon, developing countries like Egypt are less concerned about this topic. This study has developed a system dynamic model based on a four-phase mixed methodology approach; we captured the complex interconnected interactions between supply chain performance and climate change physical risks. A cognitive map was first developed to capture the relationship between the climate change physical risks variables and the supply chains. Then, historical climate data and data from a ceramic manufacturing company were analyzed using the Statistical Package for the Social Sciences (SPSS). A case study of a ceramic manufacturing company located in Egypt is provided to show the applicability of our developed system dynamic model. Lastly, we simulated different scenarios to assess the ramifications and consequences of climate change extreme weather-related events on the manufacturing process of the selected case company. We have observed a negative impact; a decrease in the manufacturing inventory level and production rate, total received orders and sales. As far as our knowledge, our study is the first to investigate the impacts of climate change extreme weather events on supply chains located in Egypt. Our main contribution is to prove and establish awareness among business owners, organizations, decision-makers and the Egyptian government that climate change and related extreme weather events exist and disruptions due to this fast-moving phenomenon must be considered. ; DFG, 414044773, Open Access Publizieren 2021 - 2022 / Technische Universität Berlin

Female carriers of a BRCA1 or BRCA2 genetic mutation face significantly elevated risks of cancer, with 45%–65% of women developing breast cancer and 15%–39% developing ovarian cancer in their lifetimes. Prophylactic surgery options to reduce cancer risk include a bilateral mastectomy (BM), bilateral salpingo-oophorectomy (BSO), or both surgeries. No comprehensive model providing recommendations at which age to perform the surgeries to optimize quality-adjusted life years (QALYs) exists. Using available clinical data, we develop a Markov decision process model of a mutation carrier's health states and corresponding transitions, including age-dependent breast and ovarian cancer risk, distribution of each cancer subtype and stage, and mortality. We convert the problem to a linear program to solve for the optimal surgery sequence that maximizes the carrier's expected lifetime QALYs under varying assumptions about individual patient preferences on postsurgery quality of life, fertility considerations, advances in cancer screening or treatment, and others. Baseline results demonstrate that a QALY-maximizing sequence recommends BM between ages 30 and 60 and BSO after age 40. Surgeries are recommended later for BRCA2 mutation carriers, given their lower risk for both cancers compared to BRCA1 mutation carriers. We derive structural properties from the model and show that when a carrier has already undergone one surgery, there exists an optimal control limit beyond which performing the other surgery is always QALY maximizing.

ABSTRACTIn today's world economy, which is marked by intensified international trade, air cargo acts as a key facilitator. However, cargo airlines continue to struggle to be profitable because of very high asset costs and substantial demand uncertainty. To improve upon this situation, we propose an options contract. Our model captures the main features of cargo trade between an airline and a freight forwarder and allows us to derive an optimal reservation policy. We then go on to analyze the impact of overbooking on the profit of the cargo capacity provider. The model is subsequently applied to real‐life booking data provided by a major cargo carrier. This enables us to compare current contractual arrangements with the ones proven optimal in the model. A numerical study provides insights about the impact of overbooking on contract parameters and profitability. Managerial insights to be drawn conclude this study.