Developments in sensor equipment and the Internet of Things increasingly allow production facilities to be monitored and controlled remotely and in real-time. Organizations can exploit these ...opportunities to reduce costs and improve reliability by employing condition-based maintenance (CBM) policies. Another recently proposed option is to adopt condition-based production (CBP) policies that control the deterioration of equipment by dynamically adapting the production rate. This study compares their performance and introduces a fully dynamic condition-based maintenance and production (CBMP) policy that integrates both policies. Numerical results show that their cost-effectiveness strongly depends on system characteristics such as the planning time for maintenance, the cost of corrective maintenance, and the rate and volatility of the deterioration process. Integrating condition-based production decisions into a condition-based maintenance policy substantially reduces the failure risk, while fewer maintenance actions are performed. Interestingly, in some situations, the combination of condition-dependent production and maintenance even yields higher cost savings than the sum of their separate cost savings. Moreover, particularly condition-based production is able to cope with incorrect specifications of the deterioration process. Overall, there is much to be gained by making the production rate condition dependent, also, and sometimes even more so, if maintenance is already condition-based.
•We compare condition-based maintenance (CBM) with condition-based production (CBP).•CBP controls deterioration of the system by dynamically adjusting the production rate.•Condition-based maintenance is most effective for high revenue systems.•Condition-based production is most effective when failures are expensive.•CBM and CBP can enhance each other’s cost savings performance.
Planning of biorefinery operations is complicated by the stochastic nature of physical and chemical characteristics of biomass feedstock, such as, moisture level and carbohydrate content. Biomass ...characteristics affect the performance of the equipment which feed the reactor and the efficiency of the conversion process in a biorefinery. We propose a stochastic optimization model to identify a blend of feedstocks, inventory levels, and operating conditions of equipment to ensure a continuous flowing of biomass to the reactor while meeting the requirements of the biochemical conversion process. We propose a sample average approximation (SAA) of the model, and develop an efficient algorithm to solve the SAA model. A feedstock preprocessing process consists of two-stage grinding and pelleting is used to develop a case study. Extensive numerical analysis are conducted which lead to a number of observations. Our main observation is that sequencing bales based on moisture level and carbohydrate content leads to robust solutions that improve processing time and processing rate of the reactor. We provide a number of managerial insights that facilitate the implementation of the model proposed.
We examine a manufacturer's pricing strategies in a dual-channel supply chain, in which the manufacturer is a Stackelberg leader and the retailer is a follower. We show the conditions under which the ...manufacturer and the retailer both prefer a dual-channel supply chain. We examine the coordination schemes for a dual-channel supply chain and find that a manufacturer's contract with a wholesale price and a price for the direct channel can coordinate the dual-channel supply channel, benefiting the retailer but not the manufacturer. We illustrate how such a contract with a complementary agreement, such as a two-part tariff or a profit-sharing agreement, can coordinate the dual-channel supply chain and enable both the manufacturer and the retailer to be a win–win.
► We examine a Stackelberg manufacturer's pricing strategies in a dual-channel supply chain. ► Conditions under which the manufacturer and the retailer both prefer a dual-channel are indentified. ► Coordination scheme for a dual-channel supply chain is proposed. ► With complementary agreements, coordinating contracts can enable a win–win in a dual-channel.
► We propose an original way to include sustainability criteria into inventory models. ► Multiobjective optimization results enable interesting insights to be drawn. ► The proposed interactive ...procedure enables to quickly identify a suitable solution.
Research on sustainability performance has considerably enriched operations management literature in recent years. However, work with quantitative models is still scarce. This paper contributes by revisiting classical inventory methods taking sustainability concerns into account. We believe that reducing all aspects of sustainable development to a single objective is not desirable. We thus reformulate the classical economic order quantity model as a multiobjective problem. We refer to this model as the sustainable order quantity model. Then, a multi-echelon extension of the sustainable order quantity model is studied. For both models, the set of efficient solutions (Pareto optimal solutions) is analytically characterized. These results are used to provide some insights about the effectiveness of different regulatory policies to control carbon emissions. We also use an interactive procedure that allows the decision maker to quickly identify the best option among these solutions. The proposed interactive procedure is a new combination of multi-criteria decision analysis techniques.
Lateral transshipments within an inventory system are stock movements between locations of the same echelon. These transshipments can be conducted periodically at predetermined points in time to ...proactively redistribute stock, or they can be used reactively as a method of meeting demand which cannot be satisfied from stock on hand. The elements of an inventory system considered, e.g. size, cost structures and service level definition, all influence the best method of transshipping. Models of many different systems have been considered. This paper provides a literature review which categorizes the research to date on lateral transshipments, so that these differences can be understood and gaps within the literature can be identified.
In this paper, we review the contributions to date for analyzing the newsvendor problem. Our focus is on examining the specific extensions for analyzing this problem in the context of modeling ...customer demand, supplier costs, and the buyer risk profile. More specifically, we analyze the impact of market price, marketing effort, and stocking quantity on customer demand; how supplier prices can serve as a coordination mechanism in a supply chain setting; integrating alternative supplier pricing policies within the newsvendor framework; and how the buyer’s risk profile moderates the newsvendor order quantity decision. For each of these areas, we summarize the current literature and develop extensions. Finally, we also propose directions for future research.
•We investigate a two-product closed-loop supply chain model.•We compare the impact of four production control policies.•We consider fill rate, average inventory and bullwhip as performance ...indicators.•ANOVA and Bicriteria analyses were executed to evaluate the results of simulation runs.•Changeover and production capacity notably affect the closed-loop supply chain.
The paper addresses the impact of manufacturing and remanufacturing capacity in a multi-product closed-loop supply chain. In the problem under investigation, the manufacturing system of the factory node is characterized by a failure-prone production line that is not able to manufacture both types of product simultaneously. Therefore, changeover operations are needed to switch from one product type to another. Since failure events and changeover times may involve unforeseen problems, the production control policy of the factory assumes a key role to enhance both the internal and external performance of the closed-loop supply chain. For that reason, this research compares four production control policies in terms of bullwhip effect, fill rate, and average inventory levels. We consider the well-established Hedging Corridor Policy and Improved Modified Hedging Corridor Policy, and two different versions, named Closed-Loop Hedging Corridor Policy and Closed-Loop Improved Modified Hedging Corridor Policy, which adapt the original policies to the features of the closed-loop supply chain. Through an extensive experimental analysis, the results can guide managers in assessing the effects of multi-product manufacturing and remanufacturing operations on the performance of closed-loop supply chains and in comparing the effectiveness of the production control policies.
Attempts to provide safer and higher quality fresh and minimally processed produce have given rise to a wide variety of decontamination methods, each of which have been extensively researched in ...recent years. Decontamination of Fresh and Minimally Processed Produce is the first book to provide a systematic view of the different types of decontaminants for fresh and minimally processed produce. By describing the different effects - microbiological, sensory, nutritional and toxicological - of decontamination treatments, a team of internationally respected authors reveals not only the impact of decontaminants on food safety, but also on microbial spoilage, vegetable physiology, sensory quality, nutritional and phytochemical content and shelf-life. Regulatory and toxicological issues are also addressed. The book first examines how produce becomes contaminated, the surface characteristics of produce related to bacterial attachment, biofilm formation and resistance, and sublethal damage and its implications for decontamination. After reviewing how produce is washed and minimally processed, the various decontamination methods are then explored in depth, in terms of definition, generation devices, microbial inactivation mechanisms, and effects on food safety. Decontaminants covered include: chlorine, electrolyzed oxidizing water, chlorine dioxide, ozone, hydrogen peroxide, peroxyacetic acid, essential oils and edible films and coatings. Other decontamination methods addressed are biological strategies (bacteriophages, protective cultures, bacteriocins and quorum sensing) and physical methods (mild heat, continuous UV light, ionizing radiation) and various combinations of these methods through hurdle technology. The book concludes with descriptions of post-decontamination methods related to storage, such as modified atmosphere packaging, the cold chain, and modeling tools for predicting microbial growth and inactivation. The many methods and effects of decontamination are detailed, enabling industry professionals to understand the available state-of-the-art methods and select the most suitable approach for their purposes. The book serves as a compendium of information for food researchers and students of pre- and postharvest technology, food microbiology and food technology in general. The structure of the book allows easy comparisons among methods, and searching information by microorganism, produce, and quality traits.
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