Logistics Management

We review a newly proposed modeling approach for optimizing the transportation of goods within a freight transportation network. Unlike classical modeling strategies, which measure vehicle capacity needs based on the flow of shipments on a time expanded network, this approach is based on explicit consolidations of shipments. Such an approach facilitates modeling multiple operational issues, including complicated loading constraints and piecewise linear cost functions. It also leads to a significantly stronger formulation of the problem, which can in turn be easier to solve than a formulation based on the classical approach.

From an environmental perspective, green hydrogen is a promising alternative energy carrier for short-to middle-range flights. Furthermore, hydrogen produced from renewable energy releases no carbon dioxide emissions during production and use. Therefore, hydrogen is a potential solution for reducing aviation-related emissions. Besides, the economic competitiveness of hydrogen against conventional fuels, mainly influenced by the hydrogen supply chain design, will be a key determinant for future hydrogen deployment. The supply chain consists of production, compression, transportation, and liquefaction, but these components’ exact order, sizing, and location are still insecure. Different transport options exist, which are associated with various economic impacts during their purchase and use, as well as various supply chain configurations result in different overall expenses. We analyze demand and distance scenarios using an expense-oriented economic evaluation with CAPEX and OPEX to determine the best transport configuration. The total expenses of hydrogen are highly influenced by the expenses caused by energy and transport volume. Here, pipeline transportation is a promising option, as well as liquid hydrogen truck transportation in cryogenic tanks. It turns out that distance and demand for hydrogen strongly influence the choice of transportation.

Green hydrogen as an energy carrier is a beacon of hope to achieve climate goals because of its potential to reduce carbon emissions. Currently, the hydrogen demand cannot be met entirely with green hydrogen. Thus, non-green hydrogen cannot yet be waived. Consequently, this paper considers a two-stage hydrogen supply chain (SC) consisting of three manufacturers producing green, partially green, and non-green hydrogen and a retailer. In addition to retail and wholesale prices, the manufacturer of partially green hydrogen must determine how green its produced hydrogen should be. The players are under the influence of governmental instruments, i.e., taxes on producing non-fully green hydrogen and subsidies for the retailer for selling green hydrogen. In a manufacturer-led Stackelberg game, we observe that it is more purposeful to promote green technologies through incentives than to force them by taxes. For the partially green manufacturer, relying exclusively on green hydrogen is advantageous if its market share is high, if the additional costs for the conversion to green hydrogen are comparatively low, or if the green sensitivity of the customers is high.

The transition from fossil to climate-neutral energy sources and supply chains has become a pressing challenge. Green hydrogen is expected to play an important role in the decarbonization of the global economy because of its specific versatility. Given the recent imminent energy shortages in Europe, supply of green hydrogen becomes an even more important topic for European countries. Therefore, an informed search is required for international business partners supporting European energy supply in a carbon-neutral economy setting. This could include for example Latin America with access to hydrogen production, based on renewable energy. This paper outlines the green hydrogen production landscape of Latin America and current partnership projects with Europe. The collaboration between these two regions is interesting and selected for the potential in hydrogen production capacities as well as cultural and political closeness in terms of democratic rule and property right as basic requirements for successful long-term collaborations for energy supply chains. While a large number of European companies are planning to use green hydrogen, few Latin American countries like Argentina and Chile are currently producing it. Both, consumption and production capacities are expected to increase in the next years, making the design of green hydrogen supply chains an eminent topic for Latin America and Europe. For this reason, cooperation projects are deemed beneficial to both, European and Latin-American companies and institutions. In most of the observed partnership projects within this paper, European actors contribute the technology know-how and Latin American actors offer a variety of large-scale clean energy resources for future green hydrogen supply chains. Additionally, an overview of the representation of hydrogen in Latin America compared to Europe in global energy scenario studies is presented, indicating a major research gap in linking the global scenario analysis level with the described specific project and supply chain design and development level. The results obtained for the specific collaboration of Europe with Latin America can be transferred to other global regions and cooperations.

In order to reach the two-degree target set by the Paris Agreement and to avoid rising costs due to \(\mathrm {CO_2}\) allowances and taxes, \(\mathrm {CO_2}\) intensive industry sectors like cement, steel and chemicals may opt for Carbon Capture and Storage (CCS) solutions. CCS involves capturing \(\mathrm {CO_2}\) emissions at the source points, transporting it to geological storage sites and storing it their permanently. In this context, our study investigates how to design CCS-pipeline networks that connect German cement, steel and organic chemical industries to the geological storage formations provided by the Longship project, Norway. We propose a mixed-integer programming model for the design of a corresponding on- and offshore pipeline network, where seaports serve as intermediate compressor stations for the offshore pipelines. Our results show that the supply chain costs vary significantly across industries due to differences in capture costs, \(\mathrm {CO_2}\) volumes and the spatial distribution of the point sources. The supply chain costs range from 49.3 Euro per tonne for the organic chemical industry to 83.0 Euro for the steel industry and 108.7 Euro for the cement industry, respectively. With the anticipated increase in the carbon prices in the coming years, CCS might soon become economically desirable for all these industry sectors.

The implementation of Engineering Change Management (ECM) practices challenges companies as it impacts organizational, processual, and IT levels simultaneously. We analyzed the ECM implementation in a selected company from the medical device industry, answering the research question of which leading practices support their ECM process. We characterized and systemized related practices based on twelve expert interviews. The interviews were conducted based on an interview topic guide, transcribed, and analyzed with the help of qualitative content analysis. Our analysis provides deep insights into strategies for implementing or changing processes, IT systems, and organizational structures.

This essay reflects on the changes, challenges, and proposed solutions in urban mobility and logistics over time. Thereby, it aims to provide a reference framework for a wide audience of new researchers, researchers lacking a background in transport, and specialists looking for a broader perspective for inspiration. It sheds light on the past, present, and potential future developments. Particular examples are provided for the city of Kiel, Germany. Eventually, we suggest a more holistic research perspective for the logistics management community to contribute successfully to developing future urban mobility and logistics systems.

The increasing diversity of goods structures in the global supply chain has led to a need for varying inventory policies and different rail services. Understanding the heterogeneity of services in international rail transport is essential to meet these needs effectively. Existing research has focused on market segmentation in other transportation sectors, such as passenger transport, airfreight, and maritime transport. Previous research on the global supply chain and rail system has primarily been conducted isolated, whereas this paper focuses on the intersection of the two systems. This area of research is relatively novel and requires deep exploration. Using “Lean” and “Agile” principles, this paper proposes efficient, continuous replenishment, and responsive rail supply chain strategies that support market segmentation and service differentiation. These strategies ultimately contribute to integrating rail transport into the global supply chain by improving and diversifying international rail services. Additionally, managers of rail and logistics companies can benefit from this research by better understanding the value creation process, the specific characteristics of international rail transport, and the requirements of global supply chains.

Port hinterland transportation with trucks is an important part of the maritime supply chain as a significant part of supply chain costs are generated here, e.g. due to empty container transportation. Horizontal collaboration among carriers offers potential for cost reduction, but needs to be set up in a way which is fair and advantageous in the long-run for all carriers involved. In this work, a new model is developed which takes these and other realistic requirements, e.g. the use of different container types and of empty container depots, into account. The results allow to quantify the benefits of collaboration for different collaborating group sizes and under different fairness mechanisms.

In traditional machine scheduling, the focus is on determining the sequence of jobs on the machines. Meanwhile, the logistical question of how to organize the transport process between production stages frequently remains in the background. In this article, however, we consider lot streaming, offering the possibility to forward units to the next production stage before the entire production lot has been completed. Specifically, we analyze lot streaming in a hybrid flow shop where the aim is to minimize the makespan. For this purpose, two mixed-integer optimization models are developed and compared with respect to their solution quality. Based on the superior formulation, we analyze the influence of the configuration of the hybrid flow shop in terms of the number of production stages, the number of machines on the stages, and the length of the processing times on the makespan for moderate problem sizes. The results obtained highlight the importance and effect of different lot streaming scenarios in scheduling, and, in particular when the increased complexity of scheduling with sublots is worthwhile.

A critical challenge increasingly becoming part of the day-to-day industry business is reconciling competitiveness and profitability with the sustainability of industrial value creation. With the increased frequency of natural disasters caused by climate change, customer awareness of sustainability is changing. Additionally, governments are increasingly taking regulatory action to limit harmful effects of climate change. Hence, the sustainability of a company is gradually becoming a competitive advantage. Sustainable scheduling represents a short-term potential for companies. Concurrently, due to globalization, sustainable scheduling in production networks is attracting significant research interest. The complexity of these optimization problems is high because of a large number of influencing factors, e.g., the geographical location of the customers, the number and the heterogeneity of the factories. As a result, causal relationships often overlap and cannot be separated. In this article, effects are ascertained separately with the help of single-factor experiments in an extensive computational experiment for a distributed permutation flow shop scheduling problem by using a lexicographic mixed-integer-linear-programming model and fast construction heuristics. Thereby, reasoning about the cause-effect relationships is enabled, promoting the integration of problem-specific knowledge for an efficient design of metaheuristics. Furthermore, valuable insights for management and research result from the derivation of implications.

Energy efficiency is a topic that has become central among many consumers and industries. Companies need to minimize production costs and, at the same time, reduce energy consumption and follow policy measures to reduce greenhouse gas emissions. One possibility to contribute to the sustainable design of production processes is the inclusion of energy consumption as a parameter in the optimization technique used during production scheduling. Although energy-efficient scheduling and optimization have become a scientific focus in production scheduling, practical applications are limited. The motivation of this paper is to extract energy-efficient production scheduling mechanisms from the literature using a literature review and to discuss the concepts with experts from the field. Finally, discrepancies between the needs of the industry and the scientific literature are revealed, and solution approaches to remedy the differences are proposed.

Due to numerous media reports, overstocks in supply chains have recently attracted attention alongside the public sustainability debate. The goal of this paper is to aggregate the current body of knowledge and develop a better understanding regarding (1) the quantification of overstocks (what?), (2) the management approaches used (how?), and (3) the motives of managing overstocks (why?). The review synthesizes 48 relevant publications that were systematically gathered from three of the leading scientific databases. Based on the results of the review, a research agenda is derived that identifies ten particularly promising avenues for future investigations. Furthermore, the review shows that the existing knowledge about overstocks and the way they are managed is not only limited, but also very fragmented. A holistic perspective is missing, which motivates this paper to call for a conceptualization in the sense of an “overstock management” function. To initiate this process, a definition of the term is proposed.