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The purpose of this paper is to propose a holistic optimization-based framework for addressing the re-balancing problem of vehicle-sharing schemes. In order to address this issue, the problem is decomposed into three (3) sub-problems that include: (1) the dynamic prediction of vehicle demand in stations or zones (in the case of free-floating systems); (2) the optimization of the assignment of vehicles from stations/zones using the predicted demand of the first step; and (3) the optimization of the route that the re-balancing vehicle should follow, under transverse distance minimization objectives, and given the optimized assignment of the second step. As the route optimization of the rebalancing vehicle is computationally intensive, a heuristic algorithm is developed that transforms the route optimization problem into the one (1)-Commodity Pickup and Delivery Capacitated Traveling Salesman Problem. The applicability of the proposed methodology is illustrated through its application on the real case of the bike-sharing system in the city of Thessaloniki in Greece.

Variability of demand along with issues of seasonality and supply chain disruptions may lead to significant variations between the planned and required capacities of warehouse facilities. This further leads to the rise of on-demand capacity allocation issues, with supply chain stakeholders seeking to outsource their excess capacity requirements to independent warehouses. As this matching usually occurs through freight forwarders or third-party logistics operators, who may have contractual agreements with specific warehouse operators within a region, issues of bias occur with respect to the price that capacity demanders pay. In this context, this paper proposes an optimization methodology, implemented by a neutral e-marketplace, for optimizing the matches between manufacturers and warehouses under a “market-fair” contract price for both, while taking into account the market’s demand/supply ratio.

Summarization: We develop and employ a socially responsible inventory model that determines an optimal order quantity and an optimal time instance of donation, taking into account, expectations on the net stock levels at the end of the order cycles. The optimized results of the policy are compared to those derived from the implementation of two currently applied policies namely the non-donation policy and the naive policy which involves the donation of a fixed amount of the company’s produce. A main insight revealed through the implementation of the proposed policies in a numerical experimentation indicates that the employment of the proposed donation policy could potentially lead to significantly higher expected profits compared to the other two policies. Presented on: Operational Research - An International Journal

Decisions on transport policy measures have long-term and important impacts on the economy, environment and society. Transport policy measures can lock up capital for decades and cause manifold external effects. In order to allow policymakers to evaluate transport policies, the developed decision support tool facilitates the evaluation of the multidimensional impacts of the implementation of transport policies. The objective of the decision support toolset presented in this paper is to support transportation planning and design practices based on an integrated transportation analysis of the area of examination to determine the most applicable combination of mobility services. This paper provides a comprehensive description of the interactive decision support tool implemented to help cities and decision makers design their strategies and shape the urban mobility of the future.

The role of sustainability in the function of a company and more specifically a food company is pivotal for its financial performance. The environmental issues as well as the potential economic gains from the implementation of its principles ask for the use of multiple instruments that have been developed to green supply chains. Moreover, social issues also arise and involve the food companies social responsibility, as this can be realized through the supply of fresh products that meet consumption security standards. On this basis, the strategic design of these companies’ supply chains can assists them towards meeting their sustainability objectives as it may lead to the selection of transportation modes, location of entry points and distribution centers, and flows between the nodes of the networks under cost, environmental and social impact minimization criteria. Under this context the purpose of this manuscript is to develop and employ a multi-objective (namely cost, social-time and emission minimization) mixed integer linear programming decision-making model for the network design of sustainable supply chains of perishable food products. The specific model was implemented in the case of a fruits importer in the North-Eastern European region considering its geographical settings. To synopsize and according to our findings the suggested model is an easy to use decision-making tool that leads to a whole set of possible solutions incorporating trade-offs between three aspects of sustainability.

Purpose This paper aims to examine the impact of the Greek economic crisis on the sustainability of the Turkish economy. Design/methodology/approach A generalized autoregressive conditional heteroskedasticity (GARCH) model is used over the Thomson Reuter’s Turkey Index for the period of May 1999 to August 2018 using monthly data. The control variables introduced in the proposed model are the S&P 500 of the US stock market and crude oil prices which are used to isolate more general systemic factors. Findings The structural analysis of volatility with the EGARCH model has shown that current volatility is more influenced by past volatility than by previous month shocks. Research limitations/implications The results can be exploited by investors, portfolio managers and policy makers in their decision-making process. Originality/value It is a first-time effort that examines the impact of the Greek economic crisis on the sustainability of the Turkish economy. The developed methodology can be used by investors, portfolio managers and policy makers in their decision-making process.

Although the greening of the marine sector started over a decade ago, the emissions produced from ships and port operating equipment have been only recently perceived as issues to be addressed. On this basis, the International Maritime Organisation (IMO) decided to enact stricter sulphur limits on the fuel oil used by ships in Sulphur Oxide (SOx) Emission Control Areas in an effort to reduce the environmental impact of the vessel’s bunkers. In this respect, the purpose of the paper is to quantify the cost implications of the IMO revised regulations on the shippers’ traditional supply chain network design decisions through the development of a strategic Mixed Integer Linear Programming decision-support model. The applicability of the model is demonstrated on a realistic maritime supply chain operating within the East Asia—EU trade route. The results reveal that the implementation of the sulphur limits at the route’s ports may not affect the shippers’ network structure under the current fuel prices, as the optimally selected ports have cost effective hinterland transportation connections within the EU market, that make them preferable for the shipper, even though the network’s shipping costs increase.

Considering that more than 100 million EU citizens face the risk of poverty or social exclusion, while at the same time 35% of perishable food in the EU is unnecessarily discarded at supermarkets, the redistribution of the perishable food surpluses could provide an economically feasible solution towards the confrontation of poverty and the minimization of food waste. Under this context, the purpose of this paper is to propose a novel quantitative decision-making tool that optimizes a retailer’s replenishment policy for perishable products while minimizing the amount of perishable items discarded after they approach their expiration dates, through the timely donation of a part of their net stocks.

We propose an analytical modeling methodology for quantifying the impact of slow steaming on the carrier’s voyage cost and on the shipper’s total landed logistics costs. The developed methodology can be employed by a carrier and a shipper in their contract negotiations, in order for the two parties to determine how they could divide between them the savings resulted from slow steaming. We demonstrate that the impact of slow steaming and speed adjustment policies on the shippers’ total landed logistics costs tend to increase as the vessel travels towards the end of its voyage.

We develop a simulation-based optimization methodology for the joint design and planning of globalized supply chains (SCs) under minimization objectives for cost and CO2 emissions. The assumptions required for the analytical optimization of such SCs include deterministic lead times, no-backorder occurrences at central distribution facilities, and powers-of-two replenishments of inventories at the SC nodes. The paper aims to investigate whether and how will the decisions that stem from the analytical optimization process change when these assumptions are relaxed. The proposed methodology is employed in a realistic SC structure. The results reveal that (i) the optimal order cycles of the nodes of the SC are not necessarily powers of two, (ii) the central distribution facilities have the option to operate at lower service levels, (iii) the network's cost and CO2 emissions under optimality are reduced by approximately 0.9%, and (iv) the strategic network design decisions align with those of the analytical solution.

Numerous linkages among Agriculture and climate change have been identified and validated in global terms. In European Union, the economic performance&ndash, carbon dioxide emission relationship has become a particularly high priority issue for Common agricultural policy within the last decade, attracting scientific interest. Within this socio&ndash, economic framework, the present work studies the relationship between agricultural carbon emissions equivalents and income per capita for the agricultural sector in different EU countries with the assistance of the nonlinear autoregressive distributed lag (NARDL) cointegration technique. Our findings validate the existence of a strong relationship between GHG emissions and agricultural income, since the cointegration among the two variables is established in all instances, while the asymmetric impact of agricultural income on carbon emissions may well provide policy makers with tools which when implemented, may well promote the increase of agricultural income along with GHG effect mitigation in a successful way.

We quantify the impact of jointly optimizing strategic network design and tactical inventory planning on the cost and CO2 emissions of multi-echelon logistics networks. The obtained insights indicate that longer optimized replenishment cycles reduce a node's transportation cost and CO2 emissions but increase its inventory costs. Moreover, under a fixed replenishment cycle, a node's service level increases when supplied by a satellite warehouse. Finally: (i) the costs of implementing optimal green network design decisions could be misleading if inventory planning is neglected, (ii) greening of supply chains could become expensive, (iii) current legislative CO2 ton prices hardly influence logistics networks.

This chapter updates the work of Rommert Dekker, Jacqueline Bloemhof-Ruwaard, and Ioannis Mallidis through the development of a hierarchical green supply chain management (GSCM) framework. It presents an extensive literature review of recent and representative academic research efforts, at assisting supply chain stakeholders in providing an outline of the main decisions that may affect the environmental performance of all three main physical drivers of a supply chain, namely products, facilities, and transportation. The chapter identifies the quantitative models employed for quantifying this environmental performance, and also how these decisions could transcend the strategic, tactical, and operational decision phases. The work of Dekker, Bloemhof, and Mallidis is also extended through the consideration of additional GSCM decisions, namely product design, manufacturing design and planning, transportation planning, product quality control, equipment maintenance and green work methods.

The consideration of environmental issues has emerged as a topic of critical importance for today’s globalized supply chains. The purpose of this paper is to develop a strategic-tactical decision support model to assist managers in evaluating the impact of environmental issues, related to transportation emissions, on the transport geography of a region. Specifically we provide a model that addresses: (i) supply chain network design, including port of entry and transportation mode, and (ii) decisions on using dedicated versus shared warehouses and transportation. The applicability of the proposed methodology is examined through the development of a sustainable supply chain network in the South-Eastern Europe region. The results indicate that in most cases using shared warehouses from Third Party Logistics operators improves both the cost and the environmental performance of a company. In all cases shared use of transportation operations minimizes the amount of CO2 and PM emissions generated, while dedicated use minimizes costs.

The worldwide economic growth of the last century has given rise to a vast consumption of goods while globalization has led to large streams of goods all over the world. The production, transportation, storage and consumption of all these goods, however, have created large environmental problems. Today, global warming, created by large scale emissions of greenhouse gasses, is a top environmental concern. Governments, action groups and companies are asking for measures to counter this threat. Operations research has a long tradition in improving operations and especially in reducing costs. In this paper, we present a review that highlights the contribution of operations research to green logistics, which involves the integration of environmental aspects in logistics. We give a sketch of the present and possible developments, focussing on design, planning and control in a supply chain for transportation, inventory of products and facility decisions. While doing this, we also indicate several areas where environmental aspects could be included in OR models for logistics. Highlights ¿ Operations Research has many contributions to green logistics, like efficient use of equipment, optimization of speeds, determination of shortest routes and more efficient transportation concepts. ¿ Greening of transportation is not only a matter of less energy consuming equipment, but also of using that equipment efficiently. This can be achieved by Operations Research techniques, including revenue management. ¿ Operations Research can both help in reducing greenhouse gas emissions by making operations more efficient, as well as showing the trade-offs between costs and emissions. Quite often it appears that a small increase in costs can lead to a substantial reduction in greenhouse gas emissions. ¿ Operations Research methods allow an optimization of a whole supply chain, and can therefore also help in finding the most environmental friendly set-up.